This task documents the following user stories: RHODS-163, RHODS-162, RHODS-147, RHODS-143, RHODS-142, RHODS-165, RHODS-164

Specifically, this is to document how to define things like environment variables that may be required to run notebooks, but that users may not want to hard code.

This should probably be a reference and at least one procedure - reference for the launcher page and its contents, and procedures for filling out the launcher and possibly for calling an environment variable from inside the notebook.