Ensure compliance with MediaWiki API:Client code/Gold standard

[siznax]

See https://www.mediawiki.org/wiki/API:Client_code/Gold_standard

[siznax]

From https://www.mediawiki.org/wiki/API:Client_code/Evaluations:

Does it, at the minimum, handle logins, cookies, and continuations? (Even "syntactic sugar"-type libraries should do at least 2 of these.)

This will be a blocker until there is clear justification for adding these features, which may not be appropriate for this library. Although, we should support at least continuations.