Respect the (NSDictionary *)syncedPropertiesDictionary while syncing back from dropbox

[vijayj]

We are using the - (NSDictionary *)syncedPropertiesDictionary:(NSDictionary *)propertiesByName to only sync a few selected attributes with dropbox. This works great when syncing from client to dropbox.
However when you try resyncing from dropbox, the method in NSManagedObject+ParcelKit.m
- (void)pk_setPropertiesWithRecord:(DBRecord *)record syncAttributeName:(NSString *)syncAttributeName
does not use the keys from syncedPropertiesDictionary to sync. It would be nice if the setPropertiesWithRecord method can use the syncedPropertiesDictionary so that we can sync up partial attributes/relationships from the dictionary

[vijayj]

I think I have a fix. For some reason, I can't make a simple pull request to this branch. Here's my changes

vijayj@2b77508

[daikini]

This has been fixed in c15144a