socket: add certificate-depth and cipher-list options for SSL

Change-Id: I82757f8461807301a4a4f28c4f5bf7f0ee315113
BUG: 1114604
Signed-off-by: Jeff Darcy <jdarcy@redhat.com>
Reviewed-on: http://review.gluster.org/8040
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Rajesh Joseph <rjoseph@redhat.com>
Reviewed-by: Vijay Bellur <vbellur@redhat.com>
Merge remote-tracking branch 'origin/master' into better-peer-identification