Improving Synchronizer documentation

[israel-oye]

The documentation suggest that using the Synchronizer class to handle file operations is better but further reading the docs on how to use the Synchronizer class is just so convoluted.
It was only mentioned vaguely that one could use the Synchronizer to handle uploads and downloads but was not properly explained that you have to use the SyncPolicyManager class to set an action in the Synchronizer constructor params.