Updated mediawiki/extensions
Project: mediawiki/extensions/Wikibase  851b47e701f3222366527b765fd2a4eb2f31525b

(bug 44824) Renaming entity selector widget to $.wikibase.entityselector

Fixed some documentation in addition.

Change-Id: If85b1cd0ef4d25da994cd9122a3ec474cc6b30de