ITSOL interface

[c.]

this message from Wei Jin to the maintainers list 
was rejected due to its large attachment so I moved it to the
patch tracker :

https://savannah.gnu.org/patch/index.php?8068

it might be a good starting point for Kai's project but I'd rather 
get rid of the mex files and make use of Octave's C++ API all over.

Thanks to Wei Jin for his contribution.

c.