Make help more friendly over SSH

`ssh -p 29418 localhost help` and `ssh -p 29418 localhost gerrit help`
are now more user friendly by displaying commands the user can invoke
from within this context.

Bug: issue 296
Change-Id: I62c32855cf50ff65ee225d8e5e2c14e4badcb4af
Signed-off-by: Shawn O. Pearce <sop@google.com>
1 file changed