PAT 2.0 - Add new document to website for Project Scripts

[DavidGoldwasser]

@asparke2 I assume you will be writing this. I'm adding design docs for measure internationalization in this branch. You could to the same for this as well.
https://github.com/NREL/OpenStudio-user-documentation/tree/os_2_0

I assume the documentation non writing project scripts may be under Advanced Tutorials or Reference? The use of them should fall under general PAT 2.0 documentation.