Started adding dropbox option in idiomatic. Not working yet.
Updated DropboxSDK to latest from github. Also added 64 bit archs.
Added methods to connect and disconnect from sync services.
Fixed a number of bugs related to confusion between the persistent store id, and the baseline id. The variables are now more distinct to avoid autocompletion errors.
The store metadata was not saving properly when the baseline id was nil, because writeToFile:atomically: does not handle NSNull values. Fixed.