Updated mediawiki/extensions
Project: mediawiki/extensions/MobileFrontend  c371efa94fb08f24bce6cc9dd1560c2331ba3f39

Story 1345: Redesign notifications overlay

* Separate notification code out into mobile.notifications module
* Override in beta
* Use OverlayNew
* Support back behaviour

Change-Id: I0edb2a2cf7167554ecd14f40665411e05c305d52