Static pages with underscore in title are not found

[nidico]

Static pages such as delegation_faq cannot be accessed in the file system backend and lead to a 404.

[miroslavt]

I saw that there is some idea for functionality for managing the static pages via the web interface. This idea is not implemented yet but the code for routing these management URLs messed up with static pages with underscores.

I rearranged the routing rules so that the static page management URLs are skipped. I added a comment to fix them in future. See the pull request.

[nidico]

I'm commenting in PR #676.