Add MTLIdentityMappingForClass
Use explicit mapping in MTLJSONSerializing
Use explicit mapping in managed object serializing
Merge branch '2.0-development' into explicit-mapping

Conflicts:
	Mantle.xcodeproj/project.pbxproj
Move MTLIdentityMappingForClass to category method
Add MTLMappingAdditions to Mantle.h
Fix import statements

wtf appcode?
Fix Headers
No longer allow mapping to NSNull
WS
Update README
Improve README spelling
Fix MTLJSONAdapter docs
Use arrays when removing dictionary entries
Use mutable dictionary in MTLTestModel
Merge pull request #170 from github/explicit-mapping

Explicit mapping