[WIP] pymatbridge  package

Installing pymatbridge requires knowing where matlab is installed so that a mex file can be compiled.  This initial version of the package works by hardcoding my matlab's location in a build stage. I think the right way to do this is to also add a host-matlab package, but that still leaves the issue of matlab's location being completely arbitrary, most likely user-dependent. Every user would have to create a new spec just to specify the matlab location. The good news is that I think this package will work on our cygwin stack.