Merge branch 'master', remote branch 'upstream/master'
fixes #127 . Add first user management. Only user without posts can be deleted. On top of that add some refactoring to make some code DRY
Rename activatable to activable and add ! to let
Change english and french locals. Add english translations for pt and ro with TODO so that other contributors can find the place easily
Merge pull request #128 from msevestre/multi_user

Multi user: #127