Properly set NDEBUG for release builds
Revert "Look up the entity name from the default managed object model if it's available"

This reverts commit 2753ee5d1a6cb12eb4f01e11ceec09ab846c5115.

Conflicts:
	MagicalRecord/Categories/NSManagedObject/NSManagedObject+MagicalRecord.m
Revert "Fix test for entity name no longer returning the class name by default when none is provided"

This reverts commit 26233d20530abae2e42978984a650b595ff09192.