Initialise not_used.

Will otherwise cause crash on MSVC debug build.
Changes and additions for compiling with MSVC.

* strndup implementation (me)
* getopt implementation (Berkeley 8.3)
* gettimeofday implementation, based on v_n_get_current_time from Verse
* socket manipulation winsock2 style
* winsock2 initialization in server and client main code
* CMake changes to support above changes