Add support for having all receivers deselected by default
Add support for configuring from admin panel
Fix some bugs in the submission form.

Javascript is a special kind of hell...
In creation of a Context select all receivers by default
Merge branch 'master' into feature/select_all_receivers

* master:
  Fix visualization of receivers with long name.
  fixed bug in previosu commits
  fixed a wrong english sentence
  Properly visualize the multi select options.
  implemented issue https://github.com/globaleaks/GlobaLeaks/issues/319
  Make requests timeout after 30 seconds and stop displaying progress bar.

Conflicts:
	app/templates/default/views/submission/main.html
Merge pull request #79 from globaleaks/feature/select_all_receivers

Feature/select all receivers