Improve the edx-platform Linting Experience

[feanil]

The experience around working with the quality checks in edx-platform has a lot of issues:

• It's not clear how to run the quality checks locally.
• The text of pylint checks can be kind of opaque, can we improve this?

[sarina]

I'm not sure how true this is but I've noticed (generally) make targets being inconsistent. That said I've always found make quality in the few repos I've checked recently.

Also many Makefiles lack a help target which would be... helpful to have