make hash required for message data protocols. close #631
expose left and right bar button container views. update docs. close #634
Merge branch 'develop' of https://github.com/jessesquires/JSQMessagesViewController into develop
Update README.md
add an emptyCache property to invalidation context for explicitly clearing the cache via invalidation. close #633
fix semantics regarding avatarPlaceholderImage and avatarHighlightedImage. close #624
v6.1.0
Added EVCloudKitDao as app using this library.

EVCloudKitDao is a library for simplified access to CloudKit. As a sample there is a fully functional chat demo included which is using this library
Merge pull request #655 from evermeer/patch-1

Update README. Added EVCloudKitDao as app using this library.
add migration section to README. close #663
proj settings
Merge branch 'develop' of https://github.com/jessesquires/JSQMessagesViewController into develop
Update README.md
Updated link in README for updated iOS 6 adoption stats
Merge pull request #673 from ranunez/develop

Updated link in README for updated iOS 6 adoption stats
Merge branch 'develop' of github.com:jessesquires/JSQMessagesViewController into develop