table for IGMP packet types (we treat requests as "Query or Request", as
the type doesn't say which it is).
Base the query vs. request decision on the reported length of the
packet, not the captured length.
Checksum the packet only if it's not fragmented and the captured length
is greater than or equal to the amount to be checksummed, and, for
requests where we don't wire in the length to be checksummed, base it on
the reported length of the packet, not the captured length.
svn path=/trunk/; revision=3683
Use "col_add_fstr()" to set the Info column, rather than "sprintf()"ing
to a buffer and using "col_add_str()".
Add a routine that dissects unknown types of IGMP messages, and use it
for all IGMP messages for which we don't have a dissector.
svn path=/trunk/; revision=3452
Guy Harris