Generate a basic documentation website with the mkdocs toolkit.

No content yet other than man pages.  To make the man pages render
nicely in mkdocs, I removed the static %-headers and put the code for
them into default.md.tmp.do instead.  That way, the raw input redo-*.md
files will look right in mkdocs.

Documentation/.gitignore

@@ -1,3 +1,5 @@
 *.1
 /md-to-man
 *.html
+*.man.md
+*.list