* Discard invalid Referer header.
If an invalid Referer header such as "http://example.com/bad|uri" is
provided, ignore the value of it and skip using the Host header fallback.
* refactor instantiation.
* fix typoed header name.
* clarify reaction warning, test it.
* Add a `report` reaction.
This reaction does not halt the request, but leaves it up to the app to
react on this information. This allows e.g. frameworks to ignore failures
in certain conditions.
Changes:
* Show warnings for JsonCsrtf attacks.
* do not enable parameter escaping by default, fixes#8.
* Use more specific namespace declaration in Rack::Builder configuration.
* NotimpelentedError typo fix
* add test that makes sure passingin on :track option works. related to #6.
* deal with PATH_INFO being nil, fixes#7.
* do not track HTTP_VERSION, fixes#6.
