[x] Design models to store information about assignments of city blocks to a group of users. Proposal: create an assignments model to store: city block id, date, users who are assigned, task (i.e., visit city block), status (assigned, done, etc.)
[x] Implement the model and store initial data for it (check @sofiarivas93 and @denisde21 for data about this).
[x] Implement a simple API endpoint to CRUD this model
[x] Allow the assignment to include a field of notes