Drop unnecessary CSS selectors for a.external[href^="gopher://"]
- They don't do anything anyway - gopher:// links are not styled by anything else, so they'd just get the same styles as regular external links.
- They cause problems in browsers not supporting the attribute selector (like IE6), as the browser drops the entire rule, as required by the CSS specification.
Also removed some code in monobook/IE60Fixes.css which seems to be
simply a workaround for the issue described above.