send_to_ipsc moved into the IPSC class, as well as a new class function
for the single line to write the socket. This allows for inserting a
debug logger line to dump EVERY packet transmitted on a per-IPSC basis.
This is useful when using multiple interfaces and bridge.py is employed
as an application gateway between multiple un-connected networks (like
VPNs to the real world).
Previously, an unauthenticated network used a different class that
subclassed IPSC and overrode the the three functions that affect
authentication. Now, during class instantiation ( with __init__ ), the
set of functions are “aliased” depending on whether or not the IPSC’s
auth flag is set in dmrlink.cfg
