GWT: x.x, Enable direct access to a command via URL

see:
https://groupes.renater.fr/wiki/txm-info/public/acces_direct_par_url

step 1: edition, texts
step 2: the others
step 3: add parameters
step 4: ask login if necessary

(from redmine: issue id 595, created on 2014/02/07 by Alexey Lavrentev)

• Relations:
  • relates #1087
  • child #676 (closed)
  • child #677 (closed)
  • child #1097
  • child #1298