I think that it would be useful to have an `ArcanistStatusWorkflow` which provides an `arc status` command. This command would show information about the current differential.
**Example output**
```
**NEEDS REVISION** D1234: Create an `arc status` workflow.
Commit message here.
**Reviewers**
@epriestley requested revision.
**Lint:** OKAY
**Unit:** OKAY
```