Almost latest changes from Damien to get to 3.1
Small fix from Damien
Updating the Unity package itself

Also on minor RTMP fix
Added not about 3.1 SDK requirement
Whoops. Exported unitypackage to wrong location
Reverting file modes back to 644
Merge pull request #240 from playgameservices/ios_sdk_31

Updating iOS version of the SDK to be 3.1 compatible