fix(): fail to parse responses request depending on Postman's version
fix(): fail to parse responses request depending on Postman's version

Depending on the version of Postman used, responses request are
downloaded as JSON objects or a string refering to a request object.
This caused postmanerator to fail when parsing the collection file.

Now responses request are deserialized into an emty interface, which
prevents that behavior.

Reference #16

aubm/postmanerator