Change the way of geometries transferring

Retrieve and send node geometry separately.
Also send normals of triangles, counts and colors in addition to vertices
@Benglin, I don't think that we need any. Client knows that field inside of the JSON object with some concrete name is Base64 string which represents float array and will try to parse it. We can keep calm as far as it's really float array. Every 4-byte sequence of the decoded content will be interpreted as float. So we can say that it's based on string length. Such assumption should not fail if the data is not corrupted.