Add explicit_nil_handling option to codebase

commit 430b9762c436f180db8686407b5002cb4f71e8b9
Author: Dermot Haughey <hderms@gmail.com>
Date:   Tue Jan 15 19:36:00 2013 -0600

    Add test

commit b9adb4d916ae1cf897ea2c1f39f5ad0c0def4460
Author: Dermot Haughey <hderms@gmail.com>
Date:   Tue Jan 15 19:35:50 2013 -0600

    Cleanup of code

commit 8e8a7873b48e956e4642d31265dc767b5fafb096
Author: Dermot Haughey <hderms@gmail.com>
Date:   Tue Jan 15 19:25:42 2013 -0600

    Make changes to add option