bump handlebars to 1.3.0

Change-Id: I6ee77408505bd46e8adfecbd4ab23fc00048247b
Reviewed-on: https://gerrit.instructure.com/29857
Tested-by: Jenkins <jenkins@instructure.com>
Reviewed-by: Aaron Shafovaloff <ashafovaloff@instructure.com>
Reviewed-by: Ryan Florence <ryanf@instructure.com>
Product-Review: Ryan Florence <ryanf@instructure.com>
QA-Review: Ryan Florence <ryanf@instructure.com>
Tested-by: Ryan Florence <ryanf@instructure.com>
Product-Review: Stanley Stuart <stanley@instructure.com>
QA-Review: Stanley Stuart <stanley@instructure.com>