add support for storing custom data on a MonoClass, so Unity can store classID and sealedness in there, for faster lookups
added bit field on MonoClass to indicate if the class has an IntPtr pointing to a native class that needs AssetGarbageCollection scanning
Merge pull request #122 from Unity-Technologies/liveness

Liveness
Merge pull request #117 from Unity-Technologies/monoclass-userdata

add support for storing custom data on a MonoClass, so Unity can store c...
Update OSX runtime build to use embedded clang from Unity repo.
Unbreak iphone simulator build.
Merge pull request #126 from Unity-Technologies/bundled-clang

Build OSX runtime with bundled clang environment from Unity repo
Merge pull request #123 from Unity-Technologies/unity-staging

Liveness changes