Improve customizability of generated Makefiles

[samm82]

I noticed that I could not run the generated Makefiles on my system, since I my Python used the python command, but the Makefile used python3. Based on this StackOverflow answer, we should be able to replace python3 with python, but this should be investigated further.

Regardless, this indicates a deeper problem with our Makefiles; we should be defining variables to allow the user to more easily configure them to their specific platform. An example of this would be as such:

PYTHON=python

run: build
	$(PYTHON) Control.py $(RUNARGS)

This should be extended (as applicable) to all languages, frameworks, and anything else that may vary between users. Figuring out the full extent of what this would entail is the first step to solving this issue.

[smiths]

Having our Makefiles more easily modifiable by the users makes sense to me.

In our last meeting (#3396) @balacij also mentioned the recent trend of using virtual environments for Python. Perhaps we should make that enhancement a future issue?

[samm82]

I knew there was something about Python and Makefiles that I was forgetting - thanks!