Appending only bone-vertexgroups to bone_array. This prevents Holes in mesh caused through stonger influences of other vertexgroups.
Merge remote-tracking branch 'upstream/dev' into dev
added simple skinned animation incl. .blend file with vertex groups other than bone-vertexgroups to demonstrate (fixed) exporter bug
Merge pull request #5247 from grgr/dev

blender export vertexgroup holes fixed