Simplify app code for source viewer

This fixes a reference problem I saw while testing sampler
and also make the code for turning source/css view on/off
simpler by remove manual component searched and using the
owner's $ hash instead.

Enyo-DCO-1.1-Signed-Off-By: Ben Combee (ben.combee@lge.com)
Merge pull request #56 from enyojs/simplify-sourceview

Simplify app code for source viewer