Added a README file regarding WinRT support

To note, this file is currently formatted with CRLF line endings, rather than
LF, to allow the file to be viewed with Notepad.

visualtest/launch_harness.sh

@@ -0,0 +1,6 @@
+#!/bin/bash
+./testharness.exe --config testsprite2_crashtest.config > testrun.log 2>&1
+if [ "$?" != "0" ]; then
+  echo TEST RUN FAILED (see testrun.log)
+  # report error code to CI
+fi