Autocomplete box now submits proper results with enter/clicks/submit button

The autocomplete box should now exhibit the proper behavior with respect to enter/click.

Also fix z-indexing problem.

TODO:
+ Hook autocomplete result to map on browse page so that the map is properly zoomed to autocompleted neighborhood/location. After short discussion with Chris, Bennet may be writing hooks that I can use for this, so will wait until Bennet merges his changes.