StateSpace Object / Properties not found

Hi there,
anybody in the same position, that wanted to read a state space object ?
I can comment out the throw exception on line 590 in `MatFileReader`
`throw new IllegalStateException("Properties are not found! Not sure where to look ...");` but that would get me a MLArray, which is not same as on Matlab.
I appended an example. I did the same on a mpc-object. That created a MLUInt32 [6x1 array] for the plant, which isn't excatly what I wanted (another struct would be preferably)

[statespace.zip](https://github.com/diffplug/matfilerw/files/2032461/statespace.zip)