Maximum time of synchronization implementation

There are cases that shows Confluence synchronization were hanging and Confluence still think that the process is running fine. Without intervening (restart and database modification) this process, synchronization will not stop.

This result to multiple issue such as

• Confluence lock the database table as the directory is on synchronization process
• No new data being retrieved from LDAP and will continue like this if Confluence administrator does not check the synchronization process
• Resource locked in memory
• It is necessary to change the configuration using database UPDATE query on shutdown mode

By implementing a configurable maximum time of synchronization for example 2 hours or less, we could avoid all the above issue as Confluence will give "Synchronization Failed" message instead of keep it running in the background