Changes several calls of
create_dissector_handle() to instead call
register_dissector() with a name for the dissector. Did same for
capture dissectors where spotted.
This change allows affected dissectors to be findable by calls to
find_dissector(). In turn, this opens up more command-line use for
these protocols, including fuzzshark and rawshark, as well as lua use
Where needed, move the call from the protocol handoff function to the protocol register function, and make a static variable to hold the dissector handle.