Review best practice for drafting documentation in the developer docs

[maxime-rainville]

We expect to be doing a fair bit of documentation over the next couple months. It would be helpful to agree on some common best practices when drafting doc.

Acceptance criteria

• Liaise with the Silverstripe Content Writer upfront to make sure the guide lines line ups with Silverstirpe other style guide.
• Existing documentation best practices are reviewed.
• New best practices are agreed upon.
• Validate if the generic style guide should apply to the doc and make sure relevant rules are available to the public.

Notes

• This should not encompass docblock in our PHP code. We will spin up a separate card for it.

Related

• Writing style guide doesn't match company writing style guide #473

PRs

• DOC Update writing style guide #494
• DOC Update writing style guide #512

[GuySartorelli]

PR merged.