Got Isosurface to produce images

IsosurfaceExample in plotting/James now produces images with isosurfaces
pertaining to p-value levels on a normal distribution.

This was more of a proof of concept than anything, but perhaps
isosurface can help us visualize our pdfs a bit better.
Merge branch 'master' of https://github.com/patrickeganfoley/diffusionConnectomics