3.2

This release adds a lot of functionality to the data structures, and introduces a new file format version (backwards compatible).
Now, SimpleArray can contain floats as well as ints.
The interface to python is much more transparent now.
A significant change to the previous version is the handling of ragged tensors. Now, the row splits are not padded anymore by default.
Also, the data structures are prepared for streaming output (but this is not implemented yet).