Implemented deletions.
Workaround for crazy behaviour where OHHTTPStubs would use the wrong stub.

Couldn't figure out why this happens, stubs are cleared after each test.
Replace OHHTTPStubs with CCLRequestReplay for more awesomeness.

Also to get rid of some weird race conditions.
Implemented updates for Assets.
Removed the deletion attribute from the example.
Added test for updating an entry.
Allow specifying parameters for synchronisation.
Implemented synchronisation of deletions when using queries with CDAPersistenceManager.