Updated mediawiki/extensions
Project: mediawiki/extensions/Flow  a7d234ab2154d57d83c15f6d8f411152c13fda51

Hygiene: ExtractorInterface -> Extractor

This is the only interface in Flow with Interface in its name.
Lets go for consistency and strip the Interface part from the
name.

Change-Id: Ib8c18b846d0d6890369ff3133bb95895e6152ed3