Review and unit tests for CIDR exit policy and policy summary code

This is separate from #12378 (moved), may only be summary representation of some exit policies. (Note that in trac above it was 224/3 instead of current 224/4.

This is the former IPv4 multicast space, yet is summarized (collapsed?) to "reject all". See also [RFC3171] #12378 (moved) ...

Other half of this enhancement is review of the various policy_summarize, XXX, XXXX, with additional unit test cov erage as patch to verify and simplify policy CIDR addressing and endpoint handling (address + port).

See comments below for unit test requirements and review feedback...

Trac:
Username: anon

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