configure.py: add `-D_USE_MATH_DEFINES` manually

This adds `--ccopt -D_USE_MATH_DEFINES` manually to the .bazelrc as the
verison of bazel used on r2.1 (0.29.x) does not support platform
specific options.  This allows the windows build to function by default.

configure.py

@@ -1233,7 +1233,7 @@ def set_windows_build_flags(environ_cp):
   # Fix winsock2.h conflicts
   write_to_bazelrc(
       'build --copt=-DWIN32_LEAN_AND_MEAN --host_copt=-DWIN32_LEAN_AND_MEAN '
-      '--copt=-DNOGDI --host_copt=-DNOGDI')
+      '--copt=-DNOGDI --host_copt=-DNOGDI --copt=-D_USE_MATH_DEFINES')
   # Output more verbose information when something goes wrong
   write_to_bazelrc('build --verbose_failures')
   # The host and target platforms are the same in Windows build. So we don't