Semantic UI part 1

- Moved stylesheets to /css/
- Added Semantic to answer, changepass, deleteacc, deleteq, friends, loadquestions, login, profile, pending, register, search, viewq
- Improved style at help, notLoggedIn
- Added a top bar at index, which may be used in all pages
- Added tabs at search (and an alternative for noscript)

The brach "semantic" will not be deleted, as there is more to do.