OSX 109 fixes

mym doesn't compile (for me) on OSX 10.9. These two
fixes are required on the mym side.

I also had to follow some of the instructions from here:
http://stackoverflow.com/questions/19773916/compiling-mexopencv-in-os-x-10-9-with-xcode-5-and-matlab-r2013b
specifically updating the 10.7 in mexopts to 10.9 and replacing ""-lstdc++" with "-lc++". 
These are problems matlab problems though (and I'm running 2013a so might
be resolved now).