Suggested changes

While trying to incorporate MR into our existing app, I ran into a number of changes to the MR code that I think would be good to add to the base project. Here are 4 committed changes we are using that should help others using this library.

BTW, so far we've been pleased with the MR framework. We still don't have the full app migrated to the MR code, but what has been completed seems to be working well. I hope we can use this code to improve our overall Core Data speed and stability.