Keep old textarea format and display in HTML on tracker report

* while soap modification
* while csv import
* For new artefact from soap and csv import : TEXT is the default format

Change-Id: Id74c545f95abaa06c5577ce9336d172f52ce40a8
Merge commit 'refs/changes/17/1417/5' of ssh://gerrit.tuleap.net:29418/tuleap into stable

Change-Id: I13f23a146017fbaea9b3aa32b7e7ad1fb1891590
This is Tuleap 6.6.99.31

Change-Id: Ibeb52aa2d18d39b88a52510af262873c2697d4b1