vpython 6.10: new formula

Against system Python in a VirtualBox VM, this builds okay and I can `import visual` but `visual.sphere()` gives me a segfault in wx. Worth nothing that wx is version 3.0.1 and wxpython is 3.0.0.0, though this worked with brewed Python on my laptop.

Stack trace and console error: https://gist.github.com/anonymous/be0b7fbd366849701d0f

@sspickle, any insight?