Updated compatibility table

Closes #211
Merge branch 'develop' of github.com:braincrafted/bootstrap-bundle into develop

* 'develop' of github.com:braincrafted/bootstrap-bundle:
  Pass label_attr to checkbox_row and radio_row in choice_widget_expanded
  Adding ButtonTypeExtension which: * fixes double 'type' in markup bug * allows usage of BS-Button styled <a>-Tag * (+1 squashed commits)
  removing additional whitespaces in <button> markup
  Removed trailing whitespace for checkbox and radio
  Use preinstalled composer on Travis
  Add a Bitdeli badge to README