Fix mingw build
Windows: better net support
Remove completed TODO.win32 items
Make child_process.kill always work on windows
Define winsock error numbers
Support for non-overlapped sockets
By default windows creates sockets with the WSA_FLAG_OVERLAPPED flag set.
Because child processes don't expect to have overlapped stdio (it never happens)
it won't work with them.
Add more stuff to TODO.win32
`make test` somewhat works
Add todo file for windows port