M3UA support added

SCTP's payload protocol identifiers added.

M3UA tests provided by wireshark
http://wiki.wireshark.org/SampleCaptures#Sigtran_Protocol_Family
But RFC4666 tells that parameter 0x0002 aren't carried by M3UA, so
it's OK that tcpdump doesn't know about this identifier.


Reopened with requested corrections. Rebased on HEAD of current master.