Update jquery.fullscreen to newer version (fix IE11 support)

jquery.fullscreen wouldn't work properly in IE11. This commit fixes the
issues that were preventing it from working in that browser.

Source
* https://github.com/theopolisme/jquery-fullscreen/blob/9f8f97d127/jquery.fullscreen.js

Change log
* https://github.com/theopolisme/jquery-fullscreen/compare/v2.0.0...9f8f97d127

Change-Id: I6cb853f05ef9a464990a785827074c78ac61ac7f
mw.hook: Make hook.fire actually chainable

It was being called without being bound to the mw.hook instance,
as such the (detachable) callbackList.fireWith method (which
returns its given 'this') returned the callbackList instance
instead of the mw.hook object literal.

The tests weren't catching it because it was just checking one
can call .fire() without it crashing, but it was in fact calling
list.fire instead of hook.fire (which unlike #add and #remove are
not compatible, and we might add new methods later on).

Change-Id: If3d4dfbed494e7ff9f32514e539cfa089aea18ac
Merge "Update jquery.fullscreen to newer version (fix IE11 support)"
Merge "mw.hook: Make hook.fire actually chainable"