Allow individual steps to be tied to specific Commits

[johngrogg]

I have a repository that has been created to act as a journey through the Behavior Driven Development process, and I'd love to create a CodeTour to walk people through said jorney.

The repository has been created with specific commits that represent a moment in time developing a feature from the outside-in. Alternating between failing tests and implementations to make those tests pass.

The problem I have, is any step I create in a CodeTour is tied to the same commit as all other steps. I can use the Shell Commands feature to run a git command like git checkout T1, but that does not really facilitate the desired experience, since each step references the same fixed commit instead of the current commit.

I think this could be resolved by allowing steps to have an optional ref attribute that allows them to be associated to a specific commit instead of the main ref of the tour. Bonus points if the tour can automatically checkout the related commit.

[johngrogg]

For now, I plan to create separate tours per git tag and link to the next tour using the startTour command-link.

This will require that I export the entire set of tours and share them as a group of tours, though, which would be un-necessary if individual steps could reference individual commits.