Add preliminary MATLAB bridge

This updates old(er) work on providing a pure Cython
MEX function interface *from* MATLAB *to* Python and
TVB. There's a lot to do before it's as usuable as
other MATLAB toolboxes, but the basics are there:

- initialize Python & TVB libraries
- setup & run simulations
- transfer data back and forth between MATLAB & Python
- use other Python libraries as needed