Explicitly clarify $options arrays throughout

[patrickmj]

Lots of documentation, both prosish and in-code mentions an $options array to be passed, but explicit statements of possible options are not necessarily there.

Many of these situations are probably duplicated, where the same set of possible options are passed to many different functions (like ones for form or element building, or adding metadata to a record).

Those cases should be broken out into individual .rst files and included where useful with the .. include:: directive.