Fix fatal error when parent does not have a planning
story #2524 - see colour type at a glance on cardwall

Display a colored side bar on the left part of the card that depend of a
value of a select box field (named 'type').

Change-Id: I09996ef18a308431e4d7d12ff7cdc686f95d95a1
Merge commit 'refs/changes/20/320/2' of ssh://gerrit.tuleap.net:29418/tuleap into tuleap-stable-master

* ssh://gerrit.tuleap.net:29418/tuleap:
  story #2524 - see colour type at a glance on cardwall
  Fix fatal error when parent does not have a planning

Conflicts:
	plugins/tracker/tests/Tracker_ArtifactTest.php
Tuleap 5.11.99.12