tasks #6685: save if the fieldset is collapsed by the user

related to story #6342

+ generate print.less file to prevent 404 error.
+ remove flickering on togglers

Change-Id: Ic5f4f558c58a34c6a8a9048003f683692c71c2b7
Merge commit 'refs/changes/86/2286/6' of ssh://gerrit.tuleap.net:29418/tuleap into tuleap-stable-master

* ssh://gerrit.tuleap.net:29418/tuleap:
  tasks #6685: save if the fieldset is collapsed by the user

Change-Id: I7702caf66bf9d8d0eaac8b4e30ddd8aecaf413cf
Tuleap 6.12.99.68

Change-Id: Id5827069232625b27ccc48e5b19bfa9f65b5895b