xml.dom.minidom uses names from superseded drafts of DOM Level 3

Several public attributes and methods of xml.dom.minidom come from working drafts of DOM Level 3, and were renamed before the Recommendation was published in 2004. The code says so itself:

# DOM Level 3 attributes, based on the 22 Oct 2002 draft
# DOM Level 3 (WD 9 April 2002)

Document.errorHandler is from the same drafts; in the Recommendation it became a parameter of domConfig.

None of these names are documented, so nothing tells a user that they are neither DOM Level 1/2 (which xml.dom documents) nor DOM Level 3 (which minidom does not claim, see gh-50348).

Adding the specified names and keeping the old ones as aliases breaks nothing, and lets the documented API match the specification.

Linked PRs

• gh-156696

Comece pelo ponto de entrada xml.dom.minidom e inspecione os atributos e métodos públicos listados na issue, juntamente com seus comentários do DOM Level 3. Compare cada nome atual com o nome especificado na Recommendation; o trabalho estará concluído quando os nomes especificados estiverem disponíveis como aliases sem quebrar os nomes antigos, com cobertura adequada nos testes existentes.