Refactored GenericFilters into HoleMerger

	modified:   pandora_vision_hole_detector/CMakeLists.txt
	modified:   pandora_vision_hole_detector/include/hole_fusion_node/hole_fusion.h
	renamed:    pandora_vision_hole_detector/include/hole_fusion_node/generic_filters.h -> pandora_vision_hole_detector/include/hole_fusion_node/hole_merger.h
	modified:   pandora_vision_hole_detector/package.xml
	modified:   pandora_vision_hole_detector/src/hole_fusion_node/hole_fusion.cpp
	renamed:    pandora_vision_hole_detector/src/hole_fusion_node/generic_filters.cpp -> pandora_vision_hole_detector/src/hole_fusion_node/hole_merger.cpp