Updated mediawiki/extensions
Project: mediawiki/extensions/Wikibase  e4d49594785642b3b740eedb920f532066c1f42e

Remove some outdated/ superfluous files

The old install notes are heavily outdated and and
confusing at best, while they're not really needed
(we already have a better on in the main dir).
The lib/*Settings.php files simply don't belong into
Wikibase IMO and they aren't used anywhere as far as
I see.

Change-Id: I4f70c5aa37d2a5f12076bd0f214a4aee8e5f2b7a