Some time ago there was discussion on the Mailing List to move the web site to the source code repo so that it could be contributed to via pull request. It would be nice because then we could better rely on some basic static site generation to help deal with repetitive and sometimes error prone process of updating the header for the pages.
Anyway, a few thoughts:
1. need a shell script to publish the site to svn - something like bin/publish-site.sh
2. place files in the root of the project in a directory called site/
3. if possible, do some basic site generation with maybe some groovy script or just the shell script mentioned above to inject a "header file" for each page.