Upgrade scrolling image gallery component

[jnga]

Upgrade to the latest version of the scrolling image gallery component we are using, smoothDivScroll, which appears to include a bug fix we had made independently in a fork. Also, investigate the new smoothTouchScroll to see whether it would be helpful to use for the mobile version.

[jnga]

Started looking into this for Release 2.6, but postponing for now.

The newer smoothDivScroll version requires jQuery 1.10, which won't work with the older version of Ember currently being used. Trying a slightly newer Ember version that supports jQuery 1.10 did not work.

Upgrading the Ember side of the code first and then returning to this issue might be the way to go.