GF-55832: Add enyo.perfNow (public API from enyo.bench), and use in all duration-tracking code (Animator, Async, ScrollMath, Media, Video, to avoid potential issues when system time changes.  Previous enyo.bench in dev package now aliases to enyo.perfNow.
DCO-1.1-Signed-Off-By: Kevin Schaaf <kevin.schaaf@lge.com>
GF-55832: Remove log statement.
DCO-1.1-Signed-Off-By: Kevin Schaaf <kevin.schaaf@lge.com>
Adding CHANGELOG entry for enyo.perfNow().

Enyo-DCO-1.1-Signed-Off-By: Gray Norton (gray.norton@lge.com)
Merge pull request #601 from enyojs/GF-55832-kevinpschaaf

GF-55832: Add enyo.perfNow and use in all duration tracking code.