Atoms geometry file format

From version 3.0, Atoms uses the following structure for serializing a mesh to a .geos file.
"version":  IntMetadata(2)
"children": MapMedata
             "fooNode1": MapMetadata
                         "geo": MeshMetadata
                         "cloth" BoolMeatadata
                         "material": MapMetadata
                                          "color": Vector3Metadata
                                          "diffuseTexture": ImageMetadata
                         "attributes": MapMetadata
                                          "atoms": MapMetadata
                                                      "foo_Attr1":...
                                                      "foo_Attr2":...
                                          "arnold": MapMetadata
                                                      "ai...":...
                                          ....
                       "primVars": MapMetadata:
                                          "myVar": MapMetadata
                                                      "interpolation": StringMetadata (constant/uniform/vertex/faceVarying).
                                                      "data: Metadata

                                          ...
                                          "arnold": MapMetadata
                                                      "ai...":...

                                          "renderman": MapMetadata

                                                       ...

                                          "vray": MapMetadata

                                                       ...
                         "matrix": MatrixMetadata
                         "wolrdMatrix": MatrixMetadata
                         "translation": Vector3Metadata
                         "rotation": Vector3Metadata
                         "scale": Vector3Metadata
                         "sets": StringArrayMetadata
                         "jointIndices": ArrayMetadata
                         "jointWeights": ArrayMetadata
                         "blendshapes": MapMetadata
                         "children": MapMetadata
                                        "fooChildNode1": MapMetadata
                                                      "geo": MeshMetadata

                                                       ...