Change HttpRequestMatcher interface. This new interface makes it easier to use, more intuitive. Also do a lot of clean-up and introduce AbstractHttpResponseProvider which allows us to simplify existing HttpResponseProvider a lot.
Update version to 4.0-SNAPSHOT as we changed HttpRequestMatcher interface.
Improve javadoc of HttpRequestMatcher.
Improve javadoc of HttpResponseProxy.
Improve javadoc of AbstractHttpResponseProvider
Add removal methods for query parameters and http message headers. This makes it easier to create matching requests when implementing HttpRequestMatcher instances.
Update 4.0-SNAPSHOT changelog.