* Fixed example app router-ipv6 to build under ports/win32
* Fixed example app router-mstp to build under ports/win32 with MinGW
* Added win32 builds of router-ipv6 and router-mstp to the Github pipeline
* Update address in VMAC table for IPv6
* fix compile warnings in IPv6 handler
* cleanup BIP6 PRINTF
* enable unit test for BBMD6 hander
* keylist should only return FALSE when growing fails
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Co-authored-by: Steve Karg <skarg@users.sourceforge.net>
Steve Karg