Cycles: Add dedicated nodes to split/combine vectors.

This was already possible via the RGB nodes, but that seems weird.

intern/cycles/render/nodes.h

@@ -451,6 +451,11 @@ public:
 	SHADER_NODE_CLASS(CombineHSVNode)
 };
 
+class CombineXYZNode : public ShaderNode {
+public:
+	SHADER_NODE_CLASS(CombineXYZNode)
+};
+
 class GammaNode : public ShaderNode {
 public:
 	SHADER_NODE_CLASS(GammaNode)
@@ -471,6 +476,11 @@ public:
 	SHADER_NODE_CLASS(SeparateHSVNode)
 };
 
+class SeparateXYZNode : public ShaderNode {
+public:
+	SHADER_NODE_CLASS(SeparateXYZNode)
+};
+
 class HSVNode : public ShaderNode {
 public:
 	SHADER_NODE_CLASS(HSVNode)