List GUIDs

I'm working with a site that has had many of it's list titles changed to present cleaner URLs. For whatever reason this means that the getByTitle() endpoint for lists doesn't work with these lists.

I propose adding an optional 'list_type_guid' property to the maps, and preferring that over the list names in API calls when it's available. Also, updating the debug info tab to use and display the GUID, so that it works more reliably.