In the case of the MingW compiler, can't assume DLL_EXPORT implies USE_ANSI_C.
Warning instead of error for testlo under Windows for UDP socket not available.

Since this case is not testable, no point always having testlo fail.  It
accesses an internal variable that's not really part of the API, and
therefore isn't exported by the DLL under Windows.
testlo: The .exe extension is needed to execute subtest.
Explicit cast of time() output to long int.

Fixes a warning on MingW, where time_t does not cast implicitly without
warning.
Fix spawning of subtest on Windows.

Seems that subtest won't run under MSYS/MingW environment without
specifying the full path.  This patch adds a few output messages from
subtest to show that it is running.
cpp_test.c: Don't call exit(), use return instead.
Update TODO.
Fix a name in the AUTHORS file.  (Sorry Joe!)