Updated mediawiki/extensions
Project: mediawiki/extensions/WikibaseDatabase  425b50c6b7fbb844ee19eb5d7f3a407fcdf6eaa1

Improve docs with links for mysql and sqlite

Various links to the relevant parts of
the sqlite and mysql site.

These references will make it a lot easier when bug
fixing

Change-Id: If9f955f69f98b303272b38093f5850c31b8f78e1