BHV-11799: Add new sample to test DataList / Scroller interaction

In addressing BHV-11799, I found it helpful to create a sample to
exhaustively test the interaction of DataList and DataGridList
with our various scroll strategies.

Submitting this as a separate pull request so that this sample can
more easily be used to test behavior both before and after the
changes made to fix BHV-11799.

Enyo-DCO-1.1-Signed-Off-By: Gray Norton (gray.norton@lge.com)
BHV-11799: Hack to make translateOptimized work in Testbed sample

Our beautiful, elegant scheme for switching strategies fell over
because translateOptimized needs to be set on the strategy, not on
the scroller. This hack hard-codes a tweak to make it work.

Enyo-DCO-1.1-Signed-Off-By: Gray Norton (gray.norton@lge.com)
Merge pull request #916 from enyojs/BHV-11799-b-graynorton

BHV-11799: Add new sample to test DataList / Scroller interaction

Merging sample safely.