The registered_delivery field in SMPP message is a toggle on/off, this
patch adds two new definition so we don't have to use magic numbers from
the code.
Change-Id: I5b3afff1b3b77cccd949e0606914c7ac3ba6114c
Add special message attributes definitions that are associated with the
short message. Thus, we can get rid of magic numbers in our codebase.
Change-Id: I91afd8b462b8fd3b2c4c5b54f4eeb7ec5b730b65