New User scopes

We've added a few new user scopes for 3rd party applications that want very specific user functionality. The user:email scope gives apps read-only access to a user's private email addresses. The user:follow scope lets a user follow and unfollow other users.

This should help keep applications from requiring the user scope, which can be potentially dangerous.

We also added a read-only endpoint to get a user's public SSH keys.

GET https://api.github.com/users/technoweenie/keys