* harbour/source/vm/thread.c
+ added HB_MT() PRG function which exists only in MT HVM version and
can be REQUESTed from .prg code to force linking MT HVM.
* harbour/contrib/hbnetio/utils/netiosrv.prg
! fixed typo in port parameter support
* modified name of second parameter. Instead of 'address' use 'ifaddr'
(interface address) which seems to be more precise name.
* added 'request HB_MT' to protect linking with HVM without MT support.