This introduces a new page detailing how the rich text support works in

the API. It covers the text types, entries in extra_data, forcing text

types, and more.
All existing resources have had their custom docs on rich text support

removed in favor of the new page. These resources also now have the

"supports_text_types" flag set for the POST/PUT fields.
The docs generator uses this flag when building the request/response

field tables. If set, it will override the field's text type to

"Rich Text," and link to the new documentation.

Built the docs and looked at all the impacted resource docs. Things looked

fine from what I could see.
Tested that the links worked.