Improve collaboration between co-organizers

I am not sure if this point was raised in an issue already. We need to improve the tools for collaboring between organizers of a competition. Generally the interface is clumsy and the access permissions are not making it easy.

Current problems

1. Accessing task

• Accessing the tasks linked to a competition in the Resources menu is not easy, not clear.

You typically need to identify the name of the task and the number of the competition (in the URL), open the Resources menu, check for the tasks with the same name that are marked as "in use", and finally click on it to check if they are linked to the competition in question.

2. Task edition

• Being able to edit a task shared by someone?
• or being able to edit the tasks as a co-organizer?

Importantly, you may not have access to the task (and to edit it) if you are not the owner, but just a co-organizer.

Also related:

• #1078

3. Sharing server status information

This problem was solved by #2158

• #2045

4. Adding collaborators (minor)

Original issue: #1807

a) In competition.yaml

• No "organizers" field in competition.yaml

It seems that we don't have a admins or organizers field in the file competition.yaml in order to easily add other users as organizers of the challenge.

• Update unpacker v1 (admins --> collaborators): https://github.com/codalab/codabench/blob/develop/src/apps/competitions/unpackers/v1.py
• Update unpacker v2: https://github.com/codalab/codabench/blob/develop/src/apps/competitions/unpackers/v2.py
• Update the wiki: https://github.com/codalab/codabench/wiki/Yaml-Structure

b) From competition creation UI

• Organizers are not added when creating a competition using the UI

When you create a competition using the UI, you can add admins from the interface but when you save the competition, the admins are not there. Updating the competition with the admins works.

5. Select task no convenient

Not directly related to collaboration, but the editor's interface is not convenient when selecting task(s) in "Edit Phase".

• Display the description of the task in the dropdown menu to help distinguish (Solved by #2340)