Auth cleanup/fixes
Authentication improvements
Desktop notifications now focus window and room when clicked, resolves #101.
Fixed flashing window title.
Tidied up WindowView.
Fixed XMPP auth bug
Added support for configuration via environment variables.
Changed password salt config setting
Added Heroku support
Tidied up README, and added Heroku Deploy button
Fixed message avatars
Only local accounts can change their username and password
Added AccountManager to core
Prevent users from changing their username when logged in via XMPP
When a user changes their username, other users are notified.

Each room that the user is a participant will:
* emit a leave event with the old screenName
* emit a join event with the new screenName
Minor tweaks
Add edit/delete room modal
Add updating rooms
Add deleting room
Add non-minified sweetalerts. Clean up html template