tasks #6702: Color is used in Tracker

 * In artifact view
 * In tracker homepage

Change-Id: I7bc98ea6d8c6ab005e54417c24799c4760aff77c
Merge commit 'refs/changes/02/2302/4' of ssh://gerrit.tuleap.net:29418/tuleap into stable

* ssh://gerrit.tuleap.net:29418/tuleap:
  tasks #6702: Color is used in Tracker
This is Tuleap 6.12.99.52

Change-Id: I8997fd817880b21a311062ee9312ea305c5660f5