Remove lighttpd support from run-webkit-tests.

We now use apache2 everywhere. Also remove a couple of stray files from
LayoutTests/http/conf that are no longer needed.

R=eseidel@chromium.org
BUG=30536

Review URL: https://codereview.chromium.org/392013003

git-svn-id: svn://svn.chromium.org/blink/trunk@178213 bbb929c8-8fbe-4397-9dbb-9b2b20218538