DISPATCH-2103 Log actual HTTP listener port number when 0 is configured (#1425)

Unit tests and related changes for the log message amount to much of the bulk of this commit.

* Old g++ (RHEL 7) does not properly implement regexes
* On Ubuntu and rarely Fedora, and all other modern Linuxes, the qd_lws_listener_free is sometimes not called in my test. This is resolved with the .finalize, available only in LibWebSockets 3.1 (RHEL 7 has version 3.0.1)
7 files changed