[SAC] git-daemon start/restart howto (and gitdaemon group)

[Sandro Santilli]

I've just added the "gitdaemon" user to the "git" group,
giving it read-access to the git repositories managed by
Gogs. This was aimed at allowing cloning git repositories
via the "dump protocol" (git://) which seemed to be broken
for the only available case we had so far:

  git://git.osgeo.org/git/geos

But as the clone still doesn't work, with the message
"fatal: remote error: access denied or repository not exported: /git/geos"

I guess I'll need to restart the service, but dunno how the service
is started and restarted.

Could anyone please write some info about managing the daemon
on this wiki page (or a dedicated one):
https://wiki.osgeo.org/wiki/SAC:Git_Service#GIT_protocol_.28Read_Only.29

Thanks in advance.

--strk;