Create a subdissector table for juniper payload protocols.

Change-Id: I60fd9c6c486b9b3b90e32fb9ccce3973569cc2ee
Reviewed-on: https://code.wireshark.org/review/5204
Reviewed-by: Michael Mann <mmann78@netscape.net>
Petri-Dish: Michael Mann <mmann78@netscape.net>
Tested-by: Petri Dish Buildbot <buildbot-no-reply@wireshark.org>
Reviewed-by: Evan Huus <eapache@gmail.com>