RFE: Summary reporting when running multiple scenarios

[cidrblock]

As a user I want to see a summry of pass/fail per scenario when running mutiple scenarios.

Output similar to either pytest or tox would be useful when running

molecule test --all

or

molecule test --all-except default

Related #4003

[Qalthos]

Scenarios presently don't retain this information, but all scenario objects are still accessible to molecule after they finish running, so if they did hold on to their results, molecule could organize that information pretty easily.

[cidrblock]

completed