Build 0247
Add apps/dg/lib/index.rhtml to the repository.
This is needed for an sc-build. It had been fabricated by the server make,
but including it makes sc-build work independently of the traditional
Data Games server environment.
Patch XHR requests to allow sending cookies/credentials
Allow setting a document server location through url params
Automatically handle "logging in" when using a document server

[#72554506]
Better user interaction when a user loads codap directly and hasn't logged in to the document server

[#72554506]
Better url for managing documents when using a document server
Re-enable guest login while using a document server

[#72367218]