Add LICENSE-2.0.txt to make sure license is clear at the repo level for layout library

Enyo-DCO-1.1-Signed-Off-By: Ben Combee (ben.combee@lge.com)
Update sample code for layout library to stop propagation of onSetupItem events after handling them to reduce runtime of list generation.

Enyo-DCO-1.1-Signed-Off-By: Ben Combee (ben.combee@lge.com)
Merge pull request #17 from enyojs/samples-stop-prop

Samples stop prop