[Distutils] The future of invoking pip

[Chris Barker - NOAA Federal]

> In this situation, if pip's default for finding the python environment
> were to search the path for 'python' instead of using sys.executable,

One trick here -- PATH may not be the same everywhere. For instance,
on OS-X, the environment GUI programs get is entirely independent of
the shell. So, as a rule, PATH will not be "right". I don't know if
anyone tries to run pip from an IDE, but it might be worth keeping in
mind-- this issue comes up all the time with setting the Python used
by an IDE.

-CHB