Merge branch 'master' into login-with-new-username-17
Cleanup session.js code and add comments.
Cleanup userSession.js code and add comments.
Avoid using cookieStore to retrieve currentUser.

Using cookieStore to keep session-related information is dangerous,
especially if you don't have a failproof way to keep data synced between
client-side and server-side.
Add explanatory comments to Angular.js files.
Keep user's session when changing username.

Also, when the user has been saved, let's redirect to their /edit profile.
Don't use cookieStore, even if user is already authenticated.
DRY up by reusing reloadCurrentUser.
Merge pull request #18 from vitaliyg/login-with-new-username-17

Login with new username 17