Begin to display Kanban cardwall

Please note that column definitions are hard-coded.

This task is part of story #7577 display a Kanban cardwall

Change-Id: I47be719fc72b56fe97bf288b9e248614dff9d3ec
Merge commit 'refs/changes/17/3317/8' of ssh://gerrit.tuleap.net:29418/tuleap into stable

* ssh://gerrit.tuleap.net:29418/tuleap:
  Begin to display Kanban cardwall

Conflicts:
	plugins/agiledashboard/www/js/kanban/src/less/main.less
This is Tuleap 7.8.99.1

Change-Id: I31583c4d36dbafe34b7dd694da0516311595a473