New doc module in gnome-system-tools

[Daniel Nylander <info danielnylander se>]

I found that the doc module for "shares" has not been added to Damned lies
It should be listed in the same block as the other g-s-t modules, boot,
network, time, users etc.

By the way, "boot" does not compile and is not activated in the
buildsystem by default. Anyone knows why?

Regards,
Daniel