Clarify constraints on personal/work projects as demonstrations

Add a subsection about re-use of work from outside the course, something like the following, but really polish it first.

Students are allowed to use their personal and professional projects for demonstrations, subject to applicable constraints. Remember, we all seek to be ethical scientists who work with sensitive research data information, treating our research subjects and data with the respect they deserve. We aren't able to support Demonstrations with content that is HIPAA protected data, Protected Health Information (PHI), or which might violate an IRB. Please, also be mindful of any other legal or regulatory constraints which might be attached to your work (e.g., Non-Disclosure Agreements, or NDAs).