Improve README punctuation [Incidental to #154691827]

Signed-off-by: Milan Klanjsek <mklanjsek@pivotal.io>

README.md

@@ -157,7 +157,7 @@ private enterprise number, [47450][p-ent-num].
 
     <$PRI>$VERSION $TIMESTAMP $HOST $APP_NAME $PROC_ID $MSG_ID [instance@47450 director="$DIRECTOR" deployment="$DEPLOYMENT" group="$INSTANCE_GROUP" az="$AVAILABILITY_ZONE" id="$ID"] $MESSAGE
 
-An example message from diego is transmitted as...
+An example message from diego is transmitted as:
 
     <14>1 2017-01-25T13:25:03.18377Z 192.0.2.10 etcd - - [instance@47450 director="test-env" deployment="cf" group="diego_database" az="us-west1-a" id="83bd66e5-3fdf-44b7-bdd6-508deae7c786"] [INFO] the leader is [https://diego-database-0.etcd.service.cf.internal:4001]
     <14>1 2017-01-25T13:25:03.184491Z 192.0.2.10 bbs - - [instance@47450 director="test-env" deployment="cf" group="diego_database" az="us-west1-a" id="83bd66e5-3fdf-44b7-bdd6-508deae7c786"] {"timestamp":"1485350702.539694548","source":"bbs","message":"bbs.request.start-actual-lrp.starting","log_level":1,"data":{"actual_lrp_instance_key":{"instance_guid":"271f71c7-4119-4490-619f-4f44694717c0","cell_id":"diego_cell-2-41f21178-d619-4976-901c-325bc2d0d11d"},"actual_lrp_key":{"process_guid":"1545ce89-01e6-4b8f-9cb1-5654a3ecae10-137e7eb4-12de-457d-8e3e-1258e5a74687","index":5,"domain":"cf-apps"},"method":"POST","net_info":{"address":"192.0.2.12","ports":[{"container_port":8080,"host_port":61532},{"container_port":2222,"host_port":61533}]},"request":"/v1/actual_lrps/start","session":"418.1"}}