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.

android-project/default.properties

@@ -0,0 +1,11 @@
+# This file is automatically generated by Android Tools.
+# Do not modify this file -- YOUR CHANGES WILL BE ERASED!
+# 
+# This file must be checked in Version Control Systems.
+# 
+# To customize properties used by the Ant build system use,
+# "build.properties", and override values to adapt the script to your
+# project structure.
+
+# Project target.
+target=android-12