Conflicts:
	MeshLib/MeshGenerators/LayeredVolume.cpp

Conflicts:
	MeshLib/MeshGenerators/LayeredVolume.cpp

added a base class to MeshLayerMapper and LayeredVolume for handling basic functionality and class structure

reworked prims-layer-generation to work from top to bottom and prefer older (lower) layers in cases of conflicting information

Conflicts:
	Gui/VtkVis/VtkVisPipeline.cpp

Conflicts:
	MeshLib/MeshQuality/RadiusEdgeRatioMetric.cpp
	MeshLib/MeshQuality/RadiusEdgeRatioMetric.h

Conflicts:
	Tests/GeoLib/TestBoundingSphere.cpp

Conflicts:
	Tests/GeoLib/TestBoundingSphere.cpp

Conflicts:
	Tests/GeoLib/TestBoundingSphere.cpp