tasks #6612: udate style + label of the query button

+ styling of the query box (margins and colors)

Change-Id: I5fcfd1aa79fbfbe1806b451bb2f91fe245dfd9ba
Merge commit 'refs/changes/52/2252/1' of ssh://gerrit.tuleap.net:29418/tuleap into stable

* ssh://gerrit.tuleap.net:29418/tuleap:
  tasks #6612: udate style + label of the query button
This is Tuleap 6.12.99.13

Change-Id: I095f5193505273c7e8a80ab7f1861988d2876731