Bug 1156457 - Set the New Relic deploy user to "Chief"

So we don't use the default.

deployment/update/update.py

@@ -115,6 +115,7 @@ def ping_newrelic(ctx):
 
         print 'Post deployment to New Relic'
         data = urllib.urlencode({
+            'deployment[user]': 'Chief',
             'deployment[revision]': settings.UPDATE_REF,
             'deployment[application_id]': settings.NEW_RELIC_APP_ID
         })