Add some branching on clone

[pablolmiranda]

The clone feature only supports to redirect the users to nTeract, but a lot of my users want to clone and land on JupyterLab or Jupyter Classic.
I would be great if we have a way to choose what product they want to land after the clone happens.

[mpacer]

Because lab has a different model than the other front-ends we would need to start encoding lab vs. classic & nteract URL conventions.

For example, we'd need to think about how we would want to support workspaces.