Changed layout and forms in homepage

- Makes use of google's jquery now
- Moved signout to the left
- Fixed Issue #2: Added 40px margin to body to accommodate the navbar.
See:
http://stackoverflow.com/questions/11124777/twitter-bootstrap-navbar-fixed-top-overlapping-site
- Changed filter by form to center properly. See:
http://stackoverflow.com/questions/9534249/twitter-bootstrap-form-inline-stretch
- Changed layout of status posts