Major codebase rewrite: from C++ to C.

Starting at release v4.0 the codebase of Nanocubes is in the C programming language. The goal with this new implementation was to get a much finer control in all aspects of the data structure and specially on its memory aspects (allocation, layout). In our original C++ template-based implementation of Nanocubes (up to version 3.3), we implemented the Nanocube data structure on top of C++ STL (standard library) and while this was a reasonable solution at the time, it had some important downsides: (1) complex serialization which made it hard to save/load Nanocube into files; (2) variations in the internal memory layout of a Nanocube based on the specific STL implementation we used.

Improvements in web GUI, bug fixes

3.3

Updated README with 3.3 preparing for release

Release 3.2.2

Removed 3.2.1 changes