learning circles

coordinate study groups for online courses

Change docker node image to explicitly use node v16 to avoid unexpected breaking changes when the next LTS is released

Update to refactored p2pu-components and add custom search UI for courses

Add method to learning circle model to get meetings and reminders ordered by date. Closes

Serialize whole team as json and remove encoding/decoding from model and frontend component

Update survey normalization used during export to correctly determine team and use created_by as the facilitator

Revert related name on Facilitator to StudyGroup foreign key to be consistent with Django convention

Test for editing learning circle facilitators and update validation for team membership

Add test for learning circle creation with cofacilitators. Add missing validation to API.