Add an empty public/uploads/ to the repository

Folder where logos and avatars are uploaded to.
Update station and adapt code to it

Updated to a version of station with less code. Some things were simply
removed from it, a few others had to be moved to Mconf-Web temporarily.

Main changes on Mconf-Web:

- The attachments are the last big thing still in station. A few things were
  removed from there and copied to Mconf-Web temporarily, until the entire
  logic for attachments is remade.
- Reviewed ApplicationController, a bit of cleanup and refactoring.