Create change management plan for any changes made to this repo

[tareko]

To figure out a change management plan, we have to figure out:

1. What changes trigger what types of approvals?
2. Who are the people who must be involved in the approvals?

Usually, Glia assigns a clinical person and an engineering person to approve all changes except for the most minor ones (e.g., typos). This seems like a reasonable starting point.

[apopanda]

See https://en.wikipedia.org/wiki/Engineering_change_order for inspirations on what info should be present when a change is needed. Important stuff that's not immediately intuitive to me include "when to implement the change - immediately by scrapping all inventory, during the next run, during a milestone" etc.