Add my semester project contribution

[MeKHell]

This includes:

• JSONify the Admin list response using Go types instead of handcrafted strings
• Migrate the authorization checks of the admins, voters, and owners from the frontend and backend to the DELA nodes
• Migrate the management of the admins, voters, and owners from the frontend and backend to the DELA nodes
• Fix the returned forms from the DELA nodes to match more closely information required by the frontend
• Fix an issue blocking the deletion of a form
• Batch and parallelize requests for owners and voters management to increase efficiency, since the DELA REST API only allows one addition or deletion per request.
• Implement the management of the operator on the DELA node and its related test
• Migrate the management of the operator from the web backend to the DELA node
• Migrate the operator checks from the web backend to the DELA nodes
• Fix an issue in the shuffling process, not caught by tests
• Implement the required tests for the web frontend and update the old ones to match the new "protocol"
• Few frontend text updates to make them clearer
• Remove 2 ghost forms that were added due to the Admin and operator lists being implemented as forms