Major styling+jQ changes, code cleanup

Changes:
1) Fixed .collapsebutton icon bug
2) aligned layout with mockup
3) major jQ changes when sidebar slides in/out
4) fixed conflicting ids
5) clean up some code

Notes:
1) We don't need to preface selectors in themizer.css
   with #sidebar; as long as they're unique, we're OK
2) we should probably use position: fixed on sidebar