Updated mediawiki/extensions
Project: mediawiki/extensions/MobileFrontend  38994a085a0a2611b566b03285616ee65bf8d2c5

Cleanup Skin language and variants

Also introduce generic MinervaTemplate as a placeholder for
a template for a future desktop/mobile skin.

Change-Id: I2e339b52e780a686ebc77cf341e346aa90550571