Renames OutlineDetection to OutlineDiscovery

plus, alters the thresholds for RGB filters running in RGB_ONLY_MODE

	modified:   pandora_vision_hole_detector/CMakeLists.txt
	modified:   pandora_vision_hole_detector/cfg/hole_fusion_node_cfg/filters_thresholds_cfg.cfg
	modified:   pandora_vision_hole_detector/include/hole_fusion_node/depth_filters.h
	modified:   pandora_vision_hole_detector/include/hole_fusion_node/filters.h
	modified:   pandora_vision_hole_detector/include/hole_fusion_node/filters_resources.h
	modified:   pandora_vision_hole_detector/include/hole_fusion_node/hole_merger.h
	modified:   pandora_vision_hole_detector/include/utils/edge_detection.h
	modified:   pandora_vision_hole_detector/include/utils/hole_filters.h
	modified:   pandora_vision_hole_detector/include/utils/message_conversions.h
	renamed:    pandora_vision_hole_detector/include/utils/outline_detection.h -> pandora_vision_hole_detector/include/utils/outline_discovery.h
	modified:   pandora_vision_hole_detector/src/hole_fusion_node/hole_fusion.cpp
	modified:   pandora_vision_hole_detector/src/hole_fusion_node/hole_merger.cpp
	modified:   pandora_vision_hole_detector/src/utils/edge_detection.cpp
	modified:   pandora_vision_hole_detector/src/utils/hole_filters.cpp
	modified:   pandora_vision_hole_detector/src/utils/message_conversions.cpp
	renamed:    pandora_vision_hole_detector/src/utils/outline_detection.cpp -> pandora_vision_hole_detector/src/utils/outline_discovery.cpp
	modified:   pandora_vision_hole_detector/test/CMakeLists.txt
	renamed:    pandora_vision_hole_detector/test/unit/utils/outline_detection_test.cpp -> pandora_vision_hole_detector/test/unit/utils/outline_discovery_test.cpp