Log Message:
Update to 0.64. From the changelog:

[Deprecated]
  - Mixing steps with comments is not allowed in Gherkin;
    support for mixing steps and comments will be removed in v1.0

[Changed]
  - Gherkin parser refactoring for readability

[Added]
  - Support for scenario descriptions: a block of explanatory text
    between the `Scenario:` keyword and the step lines