With this patch, Pungi can invoke an arbitrary command on various
moments of the compose process. The invoked command can the decide on
what message to send (and using what messaging system).
The actual command is specified in the config file.
There is a script provided that sends the messages via fedmsg.
The documentation is updated to have details about the new config option
as well as the interface for the messaging script.
Signed-off-by: Lubomír Sedlář <lsedlar@redhat.com>
