pip python module needs version control

[karlmutch]

As a user of python variants and studioml
I want to be able to manage the pip version and versions of other hidden packages
In order that cross platform variations don't cause downstream issues when the python runtime used is not a platform specific variation

With the introduction of python3 and the confusion of pip==20.0.0 that lead to cache corruptions it has become apparent that the pip module itself does require version control in order that platform incompatibilities to be dealt with.

One could envision a new custom block of pip dependencies that are supplied by the experimenter by which are not visible in the pip freeze.