Add a 'search melcat' button

- ninja-fixed a closing h1 tag
- adjusted results_header_inner css
- added button, linking to search, to greybar on results page

Signed-off-by: William Rockwood <wrockwood@tadl.org>
Minor fix for previous commit

- Needed to also uri encode the search string, so searches
  containing '&' would not break.

Signed-off-by: William Rockwood <wrockwood@tadl.org>