Update sinon from 1.10.3 to 1.15.0

Update sinon from 1.10.3 to 1.15.0

Project
* http://sinonjs.org/
* https://github.com/cjohansen/Sinon.JS

Source code
* http://sinonjs.org/releases/sinon-1.15.0.js

Changelog
* https://github.com/cjohansen/Sinon.JS/blob/v1.15.0/Changelog.txt

Notable changes:
* 1.15.0: Deprecate sinon.mock()
* 1.12.0: Fake timers are now extracted as lolex: http://github.com/sinonjs/lolex

Change-Id: Icca3eb7ef42c0a456fd309eb0ebc09a0518517bd