[Feature Request] Focus for apps/libs

[wSedlacek]

Given the nature of Nrwl Nx and its Dependency tree it would great if this could be leveraged to focus on a specific project and its direct dependencies.

This would be useful for both apps and libs.
This would be nice if it had options to include dependencies, dependents or both.
This would be best if the settings applied didn't need to be reevaluated as dependencies change, so if I add an import to a specific library it would be nice if this would just show up without any CLI commands.

As an aside, I happened across a cool project titled git-meta for managing mono repos using submodules.
I made an issue there, twosigma/git-meta#817, which details a request for nx integration which would tackle this exact problem from a different angle.
Perhaps this idea may have a better home in in xplat rather than in git-meta. That being said I would imagine the power of automatically updating on import changes would be more difficult with submodules with probably requiring a watch command which in of it self wouldn't be the worst experience (vscode plugin anyone?)