Update trigger script for new zuul url parameter

* tools/trigger-job.py: Add a --url option which passes the required
ZUUL_URL parameter with a sane default for OpenStack Infra's
environment.

Change-Id: I2d8aa73b11b0069e31ffa599c1c9d9059919fb7a
diff --git a/tools/trigger-job.py b/tools/trigger-job.py
index 9be93a1..dff4e3f 100755
--- a/tools/trigger-job.py
+++ b/tools/trigger-job.py
@@ -42,6 +42,8 @@
                         help='Old revision (SHA)')
     parser.add_argument('--newrev', dest='newrev',
                         help='New revision (SHA)')
+    parser.add_argument('--url', dest='url',
+                        default='http://zuul.openstack.org/p', help='Zuul URL')
     parser.add_argument('--logpath', dest='logpath', required=True,
                         help='Path for log files.')
     args = parser.parse_args()
@@ -56,6 +58,7 @@
             'ZUUL_SHORT_OLDREV': args.oldrev[:7],
             'ZUUL_SHORT_NEWREV': args.newrev[:7],
             'ZUUL_COMMIT': args.newrev,
+            'ZUUL_URL': args.url,
             'LOG_PATH': args.logpath,
             }