doxygen: COLLADA entry

source/blender/collada/AnimationImporter.h

source/blender/collada/ArmatureExporter.h

source/blender/collada/ArmatureImporter.h

source/blender/collada/CameraExporter.h

source/blender/collada/DocumentExporter.h

source/blender/collada/DocumentImporter.h

source/blender/collada/EffectExporter.h

source/blender/collada/GeometryExporter.h

source/blender/collada/ImageExporter.h

source/blender/collada/InstanceWriter.h

source/blender/collada/LightExporter.h

source/blender/collada/MaterialExporter.h

source/blender/collada/MeshImporter.h

source/blender/collada/SkinInfo.h

source/blender/collada/TransformReader.h

source/blender/collada/TransformWriter.h

source/blender/collada/collada.h

source/blender/collada/collada_internal.h

source/blender/collada/collada_utils.h