major changes
- (src) one error message got more detail
- long overdue fixup to developer notes doc
plus many minor changes that have been piling up
PS: to dig into the "alliterative animal" comment, check the channel
logs around aug 23rd ;-)
- allow a mob username to be defined; all unauthenticated access will
look to gitolite like this user (if you setup apache also properly)
- update doc with more details (some repeat stuff from `man
git-http-backend` but it's probably worth having everything in one
place