Garbage collecting the LibreOffice development wiki entry pages

“Oh, it’s a dirty job but someone’s gotta do it”
— Faith No More, “We Care A Lot”

I just cleaned and sorted the LibreOffice development pages:

which still contained lots of old, obsolete and even misleading content in a huge unsorted page, which likely nobody bothered to clean up because it … was a huge unsorted page. I hope the new pages with lots of obsolete stuff killed and lots of nonessential/reference stuff moved down to the end of the page, leaving the top of the page for the essentials will make life quite a bit easier for new contributors!