Additional methods for manipulating request parameters and headers
We can now remove a cookie from the request and test if whether it exists
We can now know if a request is secure
Provide request timestamp
Make sure we can remove and discard cookies in the response, as well as add (not only set) headers

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rename : src/test/java/com/vtence/molecule/RequestTest.java => src/test/java/com/vtence/molecule/ResponseTest.java