Manage collaborators

[git-voo]

Implemented

• View the list of contributors
• invite a new member
• remove member (from UI)
• error display on UI
• permissions:
  • only the Owner and Leader can view the removebutton
  • only the Owner and Leader can add new members

Pending Implementation

• [x] - remove member from DB
• [ ] - revoke member role
• [ ] move base URL to central point (env?)
• [x] move add/remove member functions to Project class
• [x] move getProject method to Project class

Create New Issue For

• [x] populate the Collaboration tab with Project title and group title
• [x] Populate project list with DB data

[cubap]

so much good work here, but I think we need to eliminate some of the redundancies. You've already got this instinct. I'm seeing some things that are in /iiif-tools and the auth struggles should be handled already. I'm going to go PR something real quick...