Change logging in stress test

Stress tests is now using the default tempest logging in order to use
tempest.conf for configuration. Every action registers a logger for
their own (previously they reported always as "stresstest").

Cleanup function is adapted as well.

Implements: bp stress-tests

Change-Id: I571d4b1ad7ced62b5d5b3e7faf8fa1a7e5f9504e
diff --git a/etc/tempest.conf.sample b/etc/tempest.conf.sample
index 4f433a6..69f9b37 100644
--- a/etc/tempest.conf.sample
+++ b/etc/tempest.conf.sample
@@ -10,6 +10,8 @@
 # lock/semaphore base directory
 lock_path=/tmp
 
+default_log_levels=tempest.stress=INFO,amqplib=WARN,sqlalchemy=WARN,boto=WARN,suds=INFO,keystone=INFO,eventlet.wsgi.server=WARN
+
 [identity]
 # This section contains configuration options that a variety of Tempest
 # test clients use when authenticating with different user/tenant