Add a return value for branch that didn't have one but needed one for crawl restarts, finished adding documentation for VersionManager, a=chris

diff --git a/src/library/VersionManager.php b/src/library/VersionManager.php
index 7e1f9d435..4fcbf4752 100644
--- a/src/library/VersionManager.php
+++ b/src/library/VersionManager.php
@@ -487,6 +487,11 @@ class VersionManager
         }
     }
     /**
+     * Restores the version of the repository that existed at a timestamp to
+     * the managed folder. Files currently in the managed folder before the
+     * restored but which exist in the HEAD version of the repository are
+     * removed from the managed folder (kept in repository).
+     *
      * @param int $timestamp of version what to restore to
      * @param bool $lock whether or not a lock should be obtained before
      *      carrying out the operation
@@ -532,6 +537,8 @@ class VersionManager
         return self::SUCCESS;
     }
     /**
+     * Gets the most recent version timestamp of a version in the repository
+     * that is less than or equal to the searched for timestamp.
      * @param int $timestamp want to find the version in the repository
      *      closest to, but not exceeding this value.
      * @param bool $lock whether or not a lock should be obtained before
@@ -622,8 +629,13 @@ class VersionManager
         return $max_timestamp;
     }
     /**
-     * @param int $start_time
-     * @param int $end_time
+     * Gets all the versions times that exist in the repository and which are
+     * between in time two values.
+     *
+     * @param int $start_time look for timestamps in repository above or equal
+     *      this value
+     * @param int $end_timelook for timestamps in repository below or equal
+     *      this value
      * @param bool $lock whether or not a lock should be obtained before
      *      carrying out the operation
      */
@@ -668,7 +680,14 @@ class VersionManager
         return $filtered_versions;
     }
     /**
-     * @param string $hash_name
+     * Get the path in the repository archive that corresponds to the given
+     * hash name of an object that might be in the repository.
+     * Currently, the archive consists of two nested folders based on prefixes
+     * of objects stored in the repository, so this method calculates those
+     * prefixes and tacks them on to the archive path.
+     *
+     * @param string $hash_name to make a archive path for
+     * @return string path to $hash_name object in repository archive
      */
     protected function getArchivePathHashName($hash_name)
     {
@@ -678,10 +697,17 @@ class VersionManager
         return $archive_path;
     }
     /**
+     * Gets the hash file name and path within the archive repository for
+     * a file name from the managed folder that existed at timestamp
+     *
      * @param string $file name of file want to get the archive name and
      *      archive path for
-     * @param int $timestamp
-     * @param bool $make_path
+     * @param int $timestamp of version want to compute archive filename and
+     *      path for
+     * @param bool $make_path whether to make folders (if they don't exists
+     *      already) in the archive repository for the path calculated
+     * @return array [hash_name, archive_path] to use for file in the
+     *      repository for object given that version timestamp
      */
     protected function getArchiveFileAndPath($file, $timestamp,
         $make_path = false)
@@ -702,8 +728,14 @@ class VersionManager
         return [$hash_name, $archive_path];
     }
     /**
-     * @param int $timestamp
-     * @param bool $make_path
+     * Versions are stored in the version subfolder of the archive repository
+     * within a year folder within a day folder. Given a timestamp this
+     * function returns the path of the version folder it would correspond to
+     * @param int $timestamp to find version folder for
+     *
+     * @param bool $make_path whether to make folders (if they don't exists
+     *      already) in the archive repository for the path calculated
+     * @return string path to version folder
      */
     protected function getVersionPath($timestamp, $make_path = false)
     {
@@ -722,11 +754,24 @@ class VersionManager
         return $version_path;
     }
     /**
-     * @param string $file name of file
-     * @param int $timestamp
-     * @param bool $get_nearest_version
-     * @param string $path_so_far
-     * @param string $hash_path_so_far
+     * Given a file or directory and a timestamp finds the path to that
+     * file in the repository by tranversing the repository and looking
+     * the hash names of folders subfolders in the repository.
+     * The timestamp that is lookedup might not be the timestamp of the file
+     * because when created a version that file might not have changed so
+     * its old info is copied into the new version. This is why a traversal
+     * might be needed.
+     *
+     * @param string $file name of file to get path for
+     * @param int $timestamp which version in repository want to get file
+     *      for
+     * @param bool $get_nearest_version if true then if $timestamp doesn't
+     *      exist as a version get the nearest version after $timestamp
+     * @param string $path_so_far path in managed folder that this recursive
+     *      procedure has already traversed
+     * @param string $hash_path_so_far corresponding path to path_so_far but
+     *      in the archive repository
+     * @return string path to file in the archive repository
      */
     protected function getHashNamePath($file, $timestamp,
         $get_nearest_version = false, $path_so_far = "", $hash_path_so_far = "")
@@ -780,7 +825,8 @@ class VersionManager
         return $path_info;
     }
     /**
-     *
+     * Delete all the files from the managed folder which exist in the HEAD
+     * version in the archive repository
      *
      * @param bool $lock whether or not a lock should be obtained before
      *      carrying out the operation
@@ -801,10 +847,15 @@ class VersionManager
         return self::SUCCESS;
     }
     /**
-     * @param string $file
-     * @param string $target
-     * @param int $timestamp
-     * @param string $hash_name_type
+     * Copies to the target folder in the managed folder a file or
+     * directory that existed at a given timestamp in the archive repository
+     * @param string $file file name of file or direcotry to copy to managed
+     *      folder
+     * @param string $target folder to copy to
+     * @param int $timestamp which archive version of the file to copy
+     * @param string $hash_name_type either f, l, or d depending on whether
+     *      the object in the repository is known to be a file, link, or folder.
+     *      If left empty then this is looked up in the repository
      * @param bool $lock whether or not a lock should be obtained before
      *      carrying out the operation
      */
@@ -906,8 +957,10 @@ class VersionManager
     /**
      * Recursively traverse a directory structure and call a callback function
      *
-     * @param string $dir directory name
-     * @param int $timestamp
+     * @param string $dir name of folder to delete
+     * @param int $timestamp only deletes if the file existed in the version
+     *      given by the timestamp in the repository (by default this is
+     *      the timestamp asscoaited with the HEAD version)
      */
     protected function traverseUnlinkHead($dir, $timestamp = 0)
     {
@@ -941,11 +994,12 @@ class VersionManager
         return self::SUCCESS;
     }
     /**
-     * This is a function used in the process of recursively deleting a
+     * This function is used in the process of recursively deleting a
      * directory
      *
      * @param string $file_or_dir the filename or directory name to be deleted
-     * @param int $timestamp
+     * @param int $timestamp only deletes if the file existed in the version
+     *      given by the timestamp in the repository
      */
     protected function deleteVersionFileOrFolder($file_or_dir, $timestamp = 0)
     {
diff --git a/src/models/CrawlModel.php b/src/models/CrawlModel.php
index b37bb1655..4a40a2ee1 100755
--- a/src/models/CrawlModel.php
+++ b/src/models/CrawlModel.php
@@ -925,7 +925,7 @@ EOT;
                 serialize($crawl_time));
             $this->execMachines("sendStartCrawlMessage",
                 $machine_urls, serialize($params), 0, true);
-            return;
+            return true;
         }
         $statuses = CrawlDaemon::statuses();
         if ($statuses == [] && $has_queue_server != -1) {
@@ -961,7 +961,7 @@ EOT;
     }
     /**
      * Used to start QueueServers and Fetchers on current machine when
-     * it is detected that someone tried to start a crawl bbut hadn't
+     * it is detected that someone tried to start a crawl but hadn't
      * started any queue servers or fetchers.
      *
      * @param bool $has_queue_server whether current machine has a queue server