vstart_runner: add log messages to vstart_runner.py

Add log messages to indicate start and end of execution of stop.sh and
vstart.sh. Running both of these scripts is a major step in execution of
vstart_runner.py and not passing --debug makes it impossible to know
whether these scripts have started or finished running.

Signed-off-by: Rishabh Dave <ridave@redhat.com>

qa/tasks/vstart_runner.py

@@ -1107,6 +1107,7 @@ class LogRotate():
 def teardown_cluster():
     log.info('\ntearing down the cluster...')
     remote.run(args=[os.path.join(SRC_PREFIX, "stop.sh")], timeout=60)
+    log.info('\nceph cluster torn down')
     remote.run(args=['rm', '-rf', './dev', './out'])
 
 
@@ -1393,9 +1394,11 @@ def exec_test():
         if opt_verbose:
             args.append("-d")
 
+        log.info('\nrunning vstart.sh now...')
         # usually, i get vstart.sh running completely in less than 100
         # seconds.
         remote.run(args=args, env=vstart_env, timeout=(3 * 60))
+        log.info('\nvstart.sh finished running')
 
         # Wait for OSD to come up so that subsequent injectargs etc will
         # definitely succeed