Keyboard shortcuts with a "list/help" overview popup in Workflow Editor

Description of the feature request

Feature should be similar to discuss. Just hit ? to get a full list of available keyboard shortcuts (Based on: Keyboard shortcuts with a "list/help" overview popup · Issue #20 · bitrise-io/bitrise-workflow-editor · GitHub)

Essentials:

Use case / for what or how I would use it

It would be useful to make the developers’ life easier.

Ahh this would be so awesome!! :keyboard: