Project Labels in Database

[ingalls]

Context

Background Reading: tnc-ca-geo/animl-frontend#124

This PR introduces an explicit array of Project labels on the Project model in MongoDB. This has the beneficial effects of

• Cheaply (as in speed) knowing what labels are in use in a project
• Allowing Project admins to add & control labels for human reviewers that are more specific or additional to the labels that a model outputs. IE: Rat from the model vs Rattus rattus frugivorus

Actions

• Add a color field to all MLModel Categories in Mongo - https://gist.github.com/ingalls/927e2c9958976184496a9d9d19a0af1c
• Update MLModel API to allow the exposure of the color field
• Create a new Project.labels schema to hold currently active labels in the project
• Backfill Project.labels schema with the output of the current project label resolver and figure out how to backfill colours?! - https://gist.github.com/ingalls/7b7325688a6fd24e9c49cc0992530043
• When a new Image is inferenced, compare the labels to the labels currently on the project and add new labels as necessary
• Add an API to create new labels on the project for project admins
• Add an API to modify existing labels on the project for project admins
• Add an API to delete existing labels on the project for project admins