[Yaml] Document the deprecated arguments of parser and dumper?

[HeahDude]

Trying to start working on #6226 to document the new YAML flags, I'm thinking that maybe we should add a third section to the YAML component doc, something like:

YAML component:

• Introduction
• Format
• Advanced Format Using Flags
  • Parser
  • Dumper

Of courses, I could have post it in the corresponding issue but I noticed that actually this doc is missing in previous version (2.7?), since we can already use some (now deprecated) extra parameters in parse() and dump().

Shouldn't we start by documenting these parameters, then fix #6226 by adding depreciations notices?

Thanks.

EDIT

• Detail arguments and object parsing,
• Document objectForMap

[xabbuh]

Yes, I think it makes sense to document features that were available before with the old way to achieve this first.

[HeahDude]

Still needs a PR in 2.7 for object maps before we can close, I added checkboxes to the description, first checked by #6582.

[xabbuh]

The second task will be accomplished by #6590.