Rename core fixtures to match the drivetrain component names

The following changes:
  common_services_deployed -> core_deployed
  sl_deployed -> stacklight_deployed

Change-Id: I6e505d2ef96053b19b2d43b0214f5a30f71ae8ea
diff --git a/tcp_tests/tests/environment/conftest.py b/tcp_tests/tests/environment/conftest.py
index 47ca68a..a1db84c 100644
--- a/tcp_tests/tests/environment/conftest.py
+++ b/tcp_tests/tests/environment/conftest.py
@@ -17,7 +17,7 @@
 from tcp_tests.fixtures.underlay_fixtures import *  # noqa
 from tcp_tests.fixtures.rally_fixtures import *  # noqa
 from tcp_tests.fixtures.salt_fixtures import *  # noqa
-from tcp_tests.fixtures.common_services_fixtures import *  # noqa
+from tcp_tests.fixtures.core_fixtures import *  # noqa
 from tcp_tests.fixtures.openstack_fixtures import *  # noqa
 from tcp_tests.fixtures.opencontrail_fixtures import *  # noqa
 
@@ -36,9 +36,9 @@
     # salt_fixtures
     'salt_actions',
     'salt_deployed',
-    # common_services_fixtures
-    'common_services_actions',
-    'common_services_deployed',
+    # core_fixtures
+    'core_actions',
+    'core_deployed',
     # openstack_fixtures
     'openstack_actions',
     'openstack_deployed',