Remove migrated utils code

This commit removes all the utils code which has been migrated to
tempest-lib and updates the uses of it to point to the library instead.

Change-Id: I9207641aa91c0ea7feb8e067316fc220880c3a3b
diff --git a/tempest/api/messaging/test_messages.py b/tempest/api/messaging/test_messages.py
index 12a3df5..f982f59 100644
--- a/tempest/api/messaging/test_messages.py
+++ b/tempest/api/messaging/test_messages.py
@@ -15,8 +15,9 @@
 
 import logging
 
+from tempest_lib.common.utils import data_utils
+
 from tempest.api.messaging import base
-from tempest.common.utils import data_utils
 from tempest import config
 from tempest import test