load jQuery and let ReSpec wipe it out with own version

Based on conversation with Joseph Scheuhammer:
!jQuery doesn't seem to work in FF.
<script>if (typeof (jQuery) == 'undefined') … works, but not if one
asks ReSpec to save an XHTML version.  The resulting document fails to
parse at that line.
Including jquery-1.9.0 just before including ReSpec, ReSpec loads its
version of jQuery and appears to wipe out the 1.9.0 version.  And,
after publishing, the script tag for ReSpec is no longer present, and
one gets jQuery 1.9.0 from the first script tag.
some general style tweaks

reduced line-height; increased font-size in table and on code; changed
colour on code and row headers
wrap code link text in <code>