ANG-8910: Accordion should bind disabled property into headerWrapper

Fixing http://jira2.lgsvl.com/browse/ANG-8910

DCO-1.1-Signed-Off-By: Kunmyon Choi kunmyon.choi@lge.com

Conflicts:
	source/Accordion.js
Removing unnecessary comma in the Accordion Sample
Merge pull request #1335 from enyojs/ANG-8910-kunmyonchoi-master

ANG-8910: Accordion should bind disabled property into headerWrapper

Looks good!

Reviewed-by: Aaron Tam (aaron.tam@lge.com)