implement "Project" backend

[tcnichol]

Task from hackathon. Create a new object called a 'project' that is a container that will hold links to datasets, folders, files that are considered part of a given project. This should allow quick and easy access to the data, allow for search by project, and eventually handle freezing and minting of objects within a project when the project is considered 'finished.'

### Tasks

[tcnichol]

Backend routes are sort of implemented. Most are not authenticated. Project can be created and files, folders, datasets and members can be added.