html5 tt validation

Signed-off-by: Illori <illori@simplemachines.org>
Merge pull request #2088 from illori/fix_tt

html5 tt validation
Merge branch 'release-2.1' of https://github.com/SimpleMachines/SMF2.1.git into release-2.1
Do not track .gitignore anymore

Signed-off-by: Michael 'Tekkla' Zorn <tekkla@tekkla.de>