Scrape all languages of a category by default

[octopusinvitro]

For wikidata scrapers that scrape a category (for example Taiwan) it would be nice if it could automatically scrape all versions of that category in all languages available, so that we can get politicians from a category who may present in some languages but not in others.

For example, in the scraper linked above, Lee Ching-hua was removed from the Chinese page for the Category of Members of the 8th Legislative Yuan, but he was still there in the English version of the page. He indeed belonged in that term.

Since at the moment of writing this issue we were only scraping the Chinese version of that category, we lost him. If we were also scraping the English version, we wouldn't.

[octopusinvitro]

Since I want to learn to work with the Wikipedia API, and without having taken a look at the code yet, I'm scaringly and adventurously assigning myself to this one.