Proposal: Evolve Project Champion Role to Reduce/Remove Bottleneck

[adamfarley]

Summary
Currently, all/most checklist tasks relating to a release are either performed or initiated by the Release Champion.

This has caused bottlenecking when the Release champion is otherwise occupied.

We should evolve the Release Champion role to reduce/remove this risk.

Proposed Solution
As discussed in the September/October Release General Retrospective, one option is to evolve the role so that the Release Champion (RC) becomes more of a Release Coordinator (title change not necessary).

This would involve changing the Release process in these ways:

1. Allowing non-RCs to pick up checklist tasks without asking the RC first.
2. Changing the release tasks/task-clusters to be atomic and threadsafe, allowing concurrency.
3. Evolving the RC role to be "ensuring that release tasks are completed", without necessarily initiating or executing the task.
4. Developing some method of coordinating the ownership, initiation, and completion of tasks. One option is to convert the release checklist into a multi-user-friendly format that allows names to be appended to tasks, plus a pair of indicators (checkboxes maybe) to indicate a task has been started/completed.
5. (Optional) Perhaps an optional daily release scrum for those performing tasks. E.g. Slack hangout.