Build: Fix testswarm task, use API correctly
Support: Make the support matrix for iOS 6 match iOS 7 as well
Event: Call underlying stopImmediatePropagation when present

Fixes #13997
Core: Bump timeouts to stabilize doc ready test

The "document ready when jQuery loaded asynchronously" test fails all the time
in iOS7 and sometimes in other browsers. Bumping the timeouts *might* help
these other browsers to be less flakey here.
AMD: Note on AMD best practices

Fixes #14687
Closes gh-1478
Readme: updating QUnit information

updates QUnit reference site and method naming.

Closes gh-1493
CSS: Add flex-grow and flex-shrink to cssNumber

Fixes #14888
Closes gh-1536