Add docs for proper kustomization installs

[mac-chaffee]

Closes #840

This PR adds documentation for installing awx-operator natively with Kustomize, rather than requireing the user to clone the repo. This way, users can provide their own patches and additional resources on top of the base resources.

I also regenerated the table of contents and added a comment telling users how to regenerate it like #793 found.

[shanemcd]

Hello. Thanks for this, it's a great contribution. One small request, otherwise this all looks awesome.

[kurokobo]

Thanks for PR, I have two comments.

kustomize build . | kubectl apply -f -

This requires that the kustomize command have to be installed, but there is no instruction to install kustomize.
The same things can be achieved by kubectl appky -k . without kustomize command, in my opinion this is much easier than installing/using kustomize command. What do you think?

Next, create a file named awx-demo.yml in the same folder
...

  # Add this extra line:
  - awx-demo.yaml

Two filenames are not matched (yaml/yml).

[mac-chaffee]

The reason I didn't recommend using the version of kustomize that comes with kubectl is because that version is typically quite outdated. Looks like the situation is improving since kubectl v1.23 is catching up, but as recently as kubectl v1.20 is two major versions behind.

I find that the one thing harder than keeping my clusters up-to-date is making sure all my users have updated clients ;)

EDIT: oh and it's very tough to see what version of kustomize you have when using the version shipped with kubectl. You have to go to the source and look at go.mod. So quite frustrating if trying to use some newer feature of kustomize that just doesn't seem to be working.

[shanemcd]

Awesome contribution. Thanks a ton.