Add Gerrit tracking id for storyboard

This change will allow users to query Gerrit for a Storyboard story
using search string 'tr:<tracking id>' or 'story:<tracking id>'. For example
you can do a query in gerrit for 'story:2000070'.

feature reference:
https://gerrit-review.googlesource.com/Documentation/config-gerrit.html#trackingid

Change-Id: Ie6c70bd02e40a6ac3a70c9fa5a0efe33a3e8e7cb
Merge "Add Gerrit tracking id for storyboard"