The former needed the latter's .dupes to do the job, so can now just
take a method as a tool to do the job instead, letting .dupes become
private. In the process refine the munging to free enumdata.py from
having to capitalize each word in its names. This will, in due course,
let us use more natural forms in various comments. This causes no
change to generted data.
Update enumdata.py's introduction doc, mainly to reflect this but also
fixing the out-of-date names (old *_list have long been *_map) and
adding some details to other paragraphs.
Task-number: QTBUG-94460
Change-Id: If195b2e94a53a495fc4f1f216bed07a910439fa7
Reviewed-by: Ievgenii Meshcheriakov <ievgenii.meshcheriakov@qt.io>