Remove jQuery, which caused browser warnings (loading http from https).

Remove jQuery, which caused browser warnings (loading http from https).

jQuery was added in commit e8bf5d2fe2879f059ef433abaf7d3a7c858b28a8
but does not seem to have been used anywhere.

If it needs to be added again, please use a protocol-relative URL:
<script src="//ajax.googleapis.com/ajax/libs/jquery/1.2.6/jquery.min.js" type="text/javascript"></script>

Signed-off-by: Anders Kaseorg <andersk@mit.edu>