Best practices for feature flag changes and a niptuk for the code snippets

[OmarIthawi]

The documentation for feature flags mentions lms.env.json and similar files. I think it's worth mentioning (in the guideline) that Ansible is the recommended way for building such files.

Additionally, the documentations features Python code when mentioning JSON files. While one can guess and do the right thing. I'd rather see a JSON syntax instead of Python.

Python: Notice the missing double quotes " and the constant True:

FEATURES = {
    'LICENSING': True,
    ...

JSON: Notice the lowercase true and the double quotes ":

"FEATURES": {
    "LICENSING": true, 
    ...

[OmarIthawi]

@grantgoodmanedX This is related to #1589. But since it's more of a general comment I filed it as an issue.