Switch to using Oslo logging

This commit removes the tempest.common.log module and switches to
using the Oslo log module. The Oslo log module is required by
lockutils and it's dependent modules, so this patch migrates all of
Tempest to it so that there is only one logger in the project. This
also has the advantage of bringing Tempest's logging configuration
in line with other OpenStack projects.

Change-Id: I31b460e454123a4211c0a8a1dc91bbfd562ce81a
diff --git a/tempest/config.py b/tempest/config.py
index a918d0b..19170ae 100644
--- a/tempest/config.py
+++ b/tempest/config.py
@@ -23,10 +23,9 @@
 
 from oslo.config import cfg
 
-from tempest.common import log as logging
 from tempest.common.utils.misc import singleton
+from tempest.openstack.common import log as logging
 
-LOG = logging.getLogger(__name__)
 
 identity_group = cfg.OptGroup(name='identity',
                               title="Keystone Configuration Options")
@@ -603,7 +602,6 @@
     def __init__(self):
         """Initialize a configuration from a conf directory and conf file."""
         config_files = []
-
         failsafe_path = "/etc/tempest/" + self.DEFAULT_CONFIG_FILE
 
         # Environment variables override defaults...
@@ -618,8 +616,6 @@
                 'TEMPEST_CONFIG' in os.environ):
             path = failsafe_path
 
-        LOG.info("Using tempest config file %s" % path)
-
         if not os.path.exists(path):
             msg = "Config file %s not found" % path
             print(RuntimeError(msg), file=sys.stderr)
@@ -627,6 +623,9 @@
             config_files.append(path)
 
         cfg.CONF([], project='tempest', default_config_files=config_files)
+        logging.setup('tempest')
+        LOG = logging.getLogger('tempest')
+        LOG.info("Using tempest config file %s" % path)
 
         register_compute_opts(cfg.CONF)
         register_identity_opts(cfg.CONF)