translation support

see PR #411 and comment https://github.com/phiamo/MopaBootstrapBundle/commit/7000c52ea22a4e269dad8b142b09a05724aff43f#commitcomment-3789576
Merge pull request #528 from peterrehm/master

Added widget_addon to choice_widget_collapsed
Merge pull request #530 from shadypierre/patch-1

translation support
Added widget addon html