Updated mediawiki/extensions
Project: mediawiki/extensions/MobileFrontend  bcc275115c7f2700ebb17f1c4c3d8abc872824db

Story 789: First time user upload tutorial revamp

Make consistent with Commons experience

* JavaScript now runs at top of page
* New assets

To do in later commit:
* Swap out SplashScreen3.png with new asset
* Change the styling of the indicators

Change-Id: I10885b1b950e9c32242975e9c0c70f28435b0efd