Make the log message more clear.

Also add a verbose logging option.
diff --git a/mysos/scheduler/mysos_scheduler.py b/mysos/scheduler/mysos_scheduler.py
index df86660..7adbb34 100644
--- a/mysos/scheduler/mysos_scheduler.py
+++ b/mysos/scheduler/mysos_scheduler.py
@@ -168,7 +168,13 @@
            "to support metrics tracking by external utilities. The format of ExecutorInfo.source "
            "is '<prefix>.<cluster_name>.<server_id>'. This flag specifies the prefix to use in the "
            "'source' field. e.g., it can be '<availability_zone>.<mesos_cluster>'. There is no "
-           "preceding period if <prefix> is empty"
+           "preceding period if <prefix> is empty")
+
+  app.add_option(
+      '--verbose',
+      dest='verbose',
+      default=None,
+      help="Turn on verbose logging"
   )
 
   def main(args, options):
@@ -198,6 +204,9 @@
     if not options.scheduler_keypath:
       app.error('Must specify --scheduler_keypath')
 
+    if options.verbose:
+      LogOptions.set_stderr_log_level('google:DEBUG')
+
     try:
       election_timeout = parse_time(options.election_timeout)
       framework_failover_timeout = parse_time(options.framework_failover_timeout)
diff --git a/mysos/scheduler/scheduler.py b/mysos/scheduler/scheduler.py
index 0c060df..7530e2c 100644
--- a/mysos/scheduler/scheduler.py
+++ b/mysos/scheduler/scheduler.py
@@ -382,10 +382,12 @@
           log.info("Declining offer %s for %s because '%s'" % (
               offer.id.value, INCOMPATIBLE_ROLE_OFFER_REFUSE_DURATION, e))
         else:
-          log.info("Declining offer %s because no launcher can use this offer" % offer.id.value)
+          log.info("Declining offer %s because no launcher accepted this offer" % offer.id.value)
           # Mesos scheduler Python binding doesn't deal with filters='None' properly.
           # See https://issues.apache.org/jira/browse/MESOS-2567.
           filters = mesos_pb2.Filters()
+
+        log.debug(offer)
         self._driver.declineOffer(offer.id, filters)
 
   @logged