Start roughing out the changes required to make the sync process more transactional
Make sure we're using performBlock and performBlockAndWait when accessing the sync context.
Move sync change creation and saving to the NSManagedObjectContextWillSaveNotification instead of NSManagedObjectContextDidSaveNotification. This change guarantees that changes will be written out as part of the MOC saving process instead of tacked on afterwards.
Added a way to request the document sync manager to begin polling for remote changes.
Fixed an issue where the remote polling code was polling multiple times each time.
Merge branch 'develop' of github.com:nothirst/TICoreDataSync into feature/transactionalSyncProcesses

Conflicts:
	TICoreDataSync/02 Primary Classes/TICDSDocumentSyncManager.m
Removed the synchronizedMOCDidSave: notification observation method.
Latest DropboxSDk that puts DBDeltaEntry in the DropboxSDK header.
Import the DropboxSDK header in the DropboxBasedDocumentSyncManager.
Remove a method signature that for a method that no longer exists.
Removed all the duplicate Dropbox SDK files, they were causing some wonky compilation problems.
Updated the log message with more info.
Merge branch 'refs/heads/develop' into feature/transactionalSyncProcesses
Latest Dropbox SDK that adds DBDeltaEntry to the DropboxOSX header.
Updated some delegate names to more accurately reflect their position in the flow of things.
The document sync manager now prevents multiple sync operations from happening at the same time. Requests to sync while the document sync manager is syncing will result in another sync being kicked off immediately after the current sync is finished. However, if the current sync fails, additional syncs will not be started.
Fixed an issue where the polling timer wouldn't be refreshed if there was a connection error to the Dropbox delta call.
Added the new TICDSSyncTransaction class which exists to maintain data integrity with regards to applied sync changes.
Move the createSyncChange method
Use the new sync transaction functionality to bookend the sync process.