This is actually a pretty big deal, and I am seriously starting wonder
if calling this "gito*lite*" is justified anymore.
Anyway, in for a penny, in for a pound...
This patch implements a generic way to allow access control for external
commands, as long as they are invoked via ssh and present a server-side
command that contains enough information to make an access control
decision.
The first (and only, so far) such command implemented is rsync.
Please read the changes in this commit (at least the ones in conf/ and
doc/) carefully.