[1] Link with c++.lib now that it builds

- Move #include <pthread.h> inside the !def no-threads guard
- Fix test support include for Windows (including an issue introduced earlier that broke the NullablePointer requirements for min_pointer)
- Set a few expected failures, and adjust lit.cfg to set the target triple
[10] Initializer List for MSVC

- Implemented initializer_list for MSVC, it expects a publicly accessible constructor taking a pair of pointers