Add visualsearch.css minification output file

@gergely-ujvari: you need to add output targets because even the
non-sass stylesheets are processed to add cache-busting checksum
query strings to url directives and rewrite relative links based
on the output target.
Tweaked style of the tags

- Slightly smaller to better fit everywhere.
- Slightly transparent in summary view, so as not to draw to much
  attention.
- Kill the border radius.
- Improve the vertical alignemnt of the input box.

Closes #599 by squashing.