Features/prevent messages removal

* master:
  Rename image to avatars
  Create url for avatar download
  Translations to avatar
  Add social logins in avatar
  Improve design
  Add upload preview
  Move avatar upload to server side
  Upload working
  Improve interface to select avatar
  Init avatar selection

Features/avatar

Conflicts:
	client/views/avatar/avatar.html

* master:
  List only users with messages

* master:
  bump font version
  Update README.md
  Update README.md
  Update README.md
  added on the news
  added back hide button for rooms and history page link
  Fix reset password
  Fix email verification
  centralize social button on home page

* 'master' of github.com:RocketChat/Rocket.Chat:
  Update README.md
  Update README.md

Features/username

* master:
  adding static landing page

* master:
  adding static landing page
  adding static landing page