What about just using maven and adding the static pages in the build process? That way it can automatically update the current version, and various other information from the project file?
Just a thought. I don't see there being too much to the site, so plain xhtml would be feasible as well, without a generator. Once created, a properly stylesheet enabled xhtml is easy to maintain.
Pelican's main usage seems to be for blogs but it can also generate regular pages. I recently converted my personal blog to pelican. I went with Markdown as the markup language because I'm already quite familiar with it from github.
The use of pelican is dead simple. If you stick to the suggested directory structure it's all about handling files and running "make html" to generate the output which is then published to the web server.
I chose pelican because it's python based. Python's "virtualenv" tool allows to set up all the required libraries in a local folder - I wasn't able to find a 1:1 equivalent for the ruby based frameworks.