++xcconfigs
Ensure that relationships are properly updated for an object matching a uniqueness constraint

Previously, objects were added/updated, but were not not deleted if not
present in the model's relationship anymore.
Cleaned to match coding conventions
More minor spacing tweaks
Merge pull request #163
Removed some extra trailing spaces
Pipe error into tmpError when serializing child objects.
Add test for #165
Made fixes requested by @robb
Merge pull request #166 from maxgoedjen/master

Pipe error into tmpError when serializing child objects.
Use the predefined mtl_valueMappingTransformerWithDictionary in the README rather than handling the enum dictionary manually
Merge pull request #179 from dcaunt/readme-state-transformer

Use the predefined mtl_valueMappingTransformerWithDictionary in the README
Removed empty line
Merge pull request #180 from dcaunt/readme-state-transformer

Removed empty line
++xcconfigs
Remove RunUnitTests scripts

Not supported in Xcode 5's `xcodebuild`.
Merge pull request #181 from github/fix-xcodebuild

Remove RunUnitTests scripts
++xcconfigs
Update objc-build-scripts
Don't pass in -sdk (for Travis)