Updated mediawiki/extensions
Project: mediawiki/extensions/SemanticMaps  4e1a74c5ea5ba30ca4ca1c0f968f9dd2c3da908d

Use American English spelling for center

Spotted by Shirayuki on
https://translatewiki.net/wiki/Thread:Support/About_MediaWiki:Creditssource-source-work/en

Change-Id: I363b5bff220082eb53b1f8f6bafc18b8486b0d73