Added ability to remove request header
feature #102 Added ability to remove request header (gronewo)

This PR was merged into the master branch.

Discussion
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Added ability to remove request header

Use case: If you are in a mink behat context and you specify a step definition where a request header gets set. Afterwards you want to assert what happens without the header so you need a way to unset the header within the next step definition.

Commits
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2c5709d Added ability to remove request header