Use step name in backtrace and simplify the usage formatter

When cucumber-ruby-core use the row location for instantiated outline steps, the usage formatter can be simplified. Use the (expanded) step name in the backtrace to be consistent with the step location for instantiated outline steps.

Requires cucumber/cucumber-ruby-core#63.

- [X] Take advandage of that instantiated steps have the row location and revert the usage formatter to the previous version
- [X] Use the expanded name in the backtrace
- [X] Include both the expanded step and the outline step in the backtrace
- [X] Update spec and features to expect the new behavior of cucumber/cucumber-ruby-core


I'm convinced too ;)