[yocto] Two pythons

[Michael Callahan]

I just moved my project from Fido to Krogoth and now I have two
pythons (2.7 and 3).  This bumps the size of my image by approximately
25%.  What would be the most reasonable way to get back to just one
python?  Ideally I'd like a magical setting to get rid of python3
because there is no custom code for that one but I suppose with enough
work I could get all of the python2 code working with python3.

  Michael