test using the API sucessfull, assign workers almost possible
Merge remote-tracking branch 'origin/leaderboard_server' into teacher-interface

Server bugs fixed
teacher interface and server updated. TI features now available: assign citizens, view game status -> history of achievements/messages sent
. Added also the logic for those features to the server
Game status and Citizens Assign pages updated. General css bug fixes
added logic and front end to create players, cities and provinces on game set-up page. Some refacoring done in the main.css resource.
Setup game page updated, first drag and drop functionality added. Introduced also some logic
Merge branch 'teacher-interface' of https://github.com/BSG-TUDelft/Utopolis into mail
Added new fields to message: from, subject and readdate. This so we can use the same message object in player-to-player messages