Fix compilation on Linux:

- The template addition is apparently a C++ Standard thing which is a bit of a mess but the way GCC interprets it requires these.
 - In XOrg there is a struct called 'Region' which causes ambiguities. For some reason doing 'using PolyVox::Region' didn't fix it.

examples/Basic/main.cpp

@@ -159,7 +159,7 @@ int main(int argc, char *argv[])
 	createSphereInVolume(volData, 24);
 
 	//Extract the surface
-	Region region(Vector3DInt16(-1,-1,-1), Vector3DInt16(32,32,32));
+	PolyVox::Region region(Vector3DInt16(-1,-1,-1), Vector3DInt16(32,32,32));
 	SurfaceMesh<PositionMaterial> mesh;
 	//CubicSurfaceExtractor<MaterialDensityPair44> surfaceExtractor(&volData, volData.getEnclosingRegion(), &mesh);
 

library/PolyVoxCore/include/MeshDecimator.inl

@@ -112,6 +112,7 @@ namespace PolyVox
 		}
 	}
 
+	template<>
 	void MeshDecimator<PositionMaterial>::fillInitialVertexMetadata(std::vector<InitialVertexMetadata>& vecVertexMetadata)
 	{
 		vecVertexMetadata.clear();
@@ -171,6 +172,7 @@ namespace PolyVox
 		}
 	}
 
+	template<>
 	void MeshDecimator<PositionMaterialNormal>::fillInitialVertexMetadata(std::vector<InitialVertexMetadata>& vecVertexMetadata)
 	{
 		vecVertexMetadata.clear();