Shading: Add Volume Info node.

The Volume Info node provides the Color, Desnity, Flame, and Temperature
of smoke domains.

Reviewers: brecht

Differential Revision: https://developer.blender.org/D5551

release/scripts/startup/nodeitems_builtins.py

@@ -186,6 +186,7 @@ shader_node_categories = [
         NodeItem("ShaderNodeAmbientOcclusion"),
         NodeItem("ShaderNodeObjectInfo"),
         NodeItem("ShaderNodeHairInfo"),
+        NodeItem("ShaderNodeVolumeInfo"),
         NodeItem("ShaderNodeParticleInfo"),
         NodeItem("ShaderNodeCameraData"),
         NodeItem("ShaderNodeUVMap"),