Updated mediawiki/extensions
Project: mediawiki/extensions/MobileFrontend  7636042d42b47c2c9d03888e879e3f7bef471954

Story 1643: Improve typography for overlays

Improve typography for the following types of overlays:
* Notifications
* Talk
* Issues

Change-Id: I3bb1af2dca1d0c39dc1d80bac8801bc0acb1c2f2