[AUDIT PATCH] comm cleanup - src/ipc/ changes

Two patches:

patch #1:
   This builds on the changes already audited in src/comm and src/base
to implement TCP listening ports being opened with ConnAcceptor and a
Subscription (to emit the HTTP or HTTPS client connect calls).

Alex; can you check that I have understood the IPC systems correctly?

NP: There is now a possibility to implementing the UDP receivers (SNMP,
DNS, ICP, multicast ICP, HTCP) in the event subscription model as well
instead of the reader model. I have not done that though.

Amos

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