Allow Scenarios to Continue Past an Error to the next 'Given/When'.

[alistairjevans]

It would be nice to allow multiple asserts to fire in a test (to collect multiple potential problems) rather than just stop on the first failure.

Test could then stop at the next non-assert (Given/When) step.

Probably best to make this configurable.

Would need an alternative to or an update to the DefaultStepCollectionExecutionStrategy.