[TIMOB-18248] Add windows to SCons builder

To Test:

1. Download the windows folder from http://studio-jenkins.appcelerator.org/job/titanium_mobile_windows/lastSuccessfulBuild/artifact/dist/windows/*zip*/windows.zip
2. Unzip that into titanium_mobile as a "windows" directory
3. Run `scons`

The generated project should have a windows folder in it (for the windows build only)