[Bf-codereview] Double Edge Matte composite node (issue 5340048)

[xgl.asyliax at gmail.com]

Reviewers: bf-codereview_blender.org,

Description:
Patch adds Double Edge Matte compo. node.

Node takes 2 single channel inputs, outputs a single channel.

General Idea can be seen in examples on user page:
http://wiki.blender.org/index.php/User:Xgl_asyliax



Please review this at http://codereview.appspot.com/5340048/

Affected files:
   source/blender/blenkernel/BKE_node.h
   source/blender/blenkernel/intern/node.c
   source/blender/editors/space_node/drawnode.c
   source/blender/makesrna/RNA_access.h
   source/blender/makesrna/intern/rna_nodetree.c
   source/blender/makesrna/intern/rna_nodetree_types.h
   source/blender/nodes/CMakeLists.txt
   source/blender/nodes/NOD_composite.h
   source/blender/nodes/composite/nodes/node_composite_dblEdgMatte.c