Rename methods which run commands

[maxmeyer]

Summary

This PR changes the name of all methods running commands. Ping @cucumber/cucumber-ruby This will be on 1.0.0, so no breakage for now.

Details

run             -> run_command
run_simple -> run_command_and_stop

Motivation and Context

We had some issues with name clashes (e.g. #435) and personally I don't like #run_simple as method name as it hides some intent.

How Has This Been Tested?

Screenshots (if appropriate):

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)

Checklist:

• I've added tests for my code
• My change requires a change to the documentation.
• I have updated the documentation accordingly.