unified bbcode buttons for image and media
adds Api v1
run api plugin test cases with app test cases
[API] mark as read ignores send value if server value is newer
[API] adds missing user id to mark as read output
[api] adds `username` to user output
fixes merging issue
Merge branch 'feature/api' into develop
code formatting
cache smilies
performance improvements in CakeTime::timeAgoInWords

see: https://github.com/cakephp/cakephp/pull/1609
code comments
[api] error message on empty subject
[s] as shorthand for [strike] bbcode-tag
fixes missing whitespaces in [spoiler] tag