swift-2.2-branch now under restrictive change control

We have reached the point in the release management of Swift 2.2 that the 'swift-2.2-branch' branches in the various repositories are under restrictive change control. This is part of the release management process for Swift 2.2 that was documented a blog post:


At this point changes going into the swift-2.2-branch will require specific approval from the release manager.

## swift-llvm, swift-clang, swift-lldb

The LLVM, Clang, and LLDB repositories are taking very little change. Please contact the respective release manager directly about taking changes into those repositories for Swift 2.2.

## swift

For the 'swift' repository, all changes will be staged into the swift-2.2-branch using a pull request. This is for recording review of the change as well as vetting by CI before the change is merged into swift-2.2-branch.

To propose a change to be pulled in, please either (a) initiate a pull request yourself or (b) contact the release manager via email if the intent is to cherry pick a small set of changes from the master branch.

Emails should include "[Swift 2.2]" in the subject line. For larger changes, the release manager may instruct you to create a pull request directly with the template of information.

Unless the scope of the change is obvious, please include in the pull request the template of information ("Explanation", "Scope", etc) as specified in the blog post.

Any questions? Please contact the respective release manager directly.