Converting generator.py to mage

[fearful-symmetry]

This is a draft as it still has a ways to go.

Right now, we're more or less at feature parity with the existing python script. The goal is to have it also replace the functionality of make setup as well, since that's a one-time operation that doesn't really need to be a separate command.

• Add setup commands
• add type validation checks
• change user docs
• update makefiles
• remove old python
• update tests
• update the beat template stuff while we're at it

[fearful-symmetry]

So, this is far from done, but now we at least have all the setup commands we need ported over to mage. This will make it easier to standardize the beat/metricbeat make files, and should reduce some amount of boilerplate.

[fearful-symmetry]

Okay, my attempts to add some useful features like a dev vendor copy and also a vendor update seemed to be...more complicated than I expected.

[fearful-symmetry]

Slowly working on porting the test. This commit will fail Ci due to #13741. Other than that, the tests should be working with the mage script.

[fearful-symmetry]

Okay, this should pass CI. Should.

[fearful-symmetry]

Alright, there we go. The make tests aren't working on my laptop, but they're working on CI.

[fearful-symmetry]

Did a quick update to the devguide.

[fearful-symmetry]

Okay, this is about ready to go out of draft. The only thing that still bugs me is the design of the generator config, and I feel like it should be a struct instead of a map. The idea is that if we need to add configuration items later down the line, it's sort of a one-step process that requires you to just add an item to that map.

[fearful-symmetry]

CI is related to the ongoing libbeat CI issues.

[fearful-symmetry]

jenkins, test this

[fearful-symmetry]

jenkins, test this

[fearful-symmetry]

jenkins, test this