tasks #6616: change sort icons

+ tasks #6607: extract table reports options into dedicated buttons

add/remove column will be done in a next step

Change-Id: Ifa97cb62823756611bdfc4b0871713ba4f506641
Merge commit 'refs/changes/54/2254/4' of ssh://gerrit.tuleap.net:29418/tuleap into stable

* ssh://gerrit.tuleap.net:29418/tuleap:
  tasks #6616: change sort icons
This is Tuleap 6.12.99.21

Change-Id: I204d281e8d98e458533201bafc3f1d5567451a3c