* fixed problems with HistEq64Filter
* removed the old FeatureExtractor and FeatureTransformers
* renamed the patch extractors to feature extractors
* added a patch filter to PyramidFeatureExtractor
* added a FilteringFeatureExtractor that builds upon another feature extractor
* changed the Detector interface to take an image instead of a pyramid and return ClassifiedPatches
* SlidingWindowDetector now takes a PyramidFeatureExtractor instead of a feature transformer