ScenarioStepProgressFormatter

A new progress formatter similar to progress2, but with more details - like scenario names, error message after failing scenario etc.

Sample output:
```
Feature with various results in scenarios (features/scenario_with_steps.feature):
    Simple scenario with passing steps: .....
    Simple scenario with second failing step: .F
--------------------------------------------------------------------------------
FAILURE in step 'a step fails' (features/scenario_with_steps.feature:10):
Assertion Failed: XFAIL-STEP
--------------------------------------------------------------------------------

    Simple scenario with fourth failing step: ...F
--------------------------------------------------------------------------------
FAILURE in step 'a step fails' (features/scenario_with_steps.feature:18):
Assertion Failed: XFAIL-STEP
--------------------------------------------------------------------------------
```