Added skeleton for the server with MongoDB
Change textarea size
Add (somewhat useless) "Undo" button
Stub undo server
Merge branch 'server' of github.com:Chouffe/vichy into server

* 'server' of github.com:Chouffe/vichy:
  Add (somewhat useless) "Undo" button
Entering "Undo handler"
Client send doc name and dummy version
Client sends version number to server
Undo with flag but seems quite buggy at the moment
Merge branch 'server' of https://github.com/Chouffe/vichy
Merge branch 'master' of https://github.com/Chouffe/vichy