Fix typo (bullseye)
Add frontmatter for index.md
Add Debian 11 installation instructions
Latest release is now 2.8
Add Mercurial repo url.

And while there, remove the Fedora version so it doesn't get out of date
so easily.
Add ISC license for wiki although it isn't perfect for documents.
Fix omitted words, add Fedora version
Fix list, add gitignore
Initial content for Ahven wiki.