Merge pull request #356 from Pbast/XWIKI-11341

XWIKI-11341: Change color of Blog/FAQ 'Create' buttons
XWIKI-11487: Cannot use .btn-success, .btn-info, .btn-danger, .btn-warning classes in conjunction with .button class
XWIKI-11341 Change color of Blog/FAQ 'Create' button (add back .button)