Fix contextual And handling

[TitouanVanBelle]

I noticed the contextual And handling was not working when steps were using the step() method because it would set the currentContextKeyword back to nil the keyword is null when using this method.

This PR contains the fix as well as the following new scenarios

Feature: Contextual And Handling

Scenario: Contextual And Handling
Given a Given statement
And an And statement defined with the keyword Give
Then the And statement should be defined

Scenario: Contextual And Handling using the step() method
Given a Given statement using the step method in its implementation
And an And statement defined with the keyword Given
Then the And statement should be defined

[brentleyjones]

Thanks @TitouanVanBelle!