[Firebird-website] update jquery with latest version

[marius a. p. <ma...@gm...>]

Please replace jquery 1.3.1 with 1.7.x
http://docs.jquery.com/Downloading_jQuery
There are many bug fixes also performance improvements
http://blog.jquery.com/2011/11/03/jquery-1-7-released/
http://blog.jquery.com/2011/11/21/jquery-1-7-1-released/