feature/geo-rep: Fix to retain pause state of gsyncd on restart.

A new gsyncd options '--pause-on-start' is introduced. When node
reboots, if the status is paused, gsyncd is started with this
option. After gsyncd spawns worker and agent, worker will send 
SIGSTOP to negative pid of monitor to enter pause mode.

Change-Id: I5aad82c9a9fc8c243f384940b77d25e26e520d6d
BUG: 1101410
Signed-off-by: Kotresh H R <khiremat@redhat.com>
Reviewed-on: http://review.gluster.org/7885
Reviewed-by: Aravinda VK <avishwan@redhat.com>
Reviewed-by: Venky Shankar <vshankar@redhat.com>
Tested-by: Venky Shankar <vshankar@redhat.com>