Testcases for services failover

- keepalived restart # 4756965
- keepalived stop # 3385682

Changes:
- RallyManager refactored to use updated rally container with tempest
- Added 'rally.create_rally_task' and 'rally.run_task' methods to
  generate load on the OpenStack cluster with the specified task config
- new mark for test cases that configure 'rally' fixture:
  @pytest.mark.with_rally(rally_node=<str>,
                          prepare_openstack=<bool>,
                          prepare_tempest=<bool>)
- a new method common_services_deployed.check_keepalived_pillar()
  to check the keepalived pillar settings consistency
- a new fixture 'func_name' returns the current test function name
- a new method 'underlay.get_target_node_names(target='ctl')' to get
  a list of all nodes which name starts with the specified target string
- a new method underlay.delayed_call() which can postpone the specified
  shell command to run in several minutes later in the background
  on the specified node
- fixture 'grab_versions' now works also for failed tests

Change-Id: Icede63163ae0b3569e8463563cb548e2d314899d
diff --git a/tcp_tests/fixtures/rally_fixtures.py b/tcp_tests/fixtures/rally_fixtures.py
index 18fa179..335ab88 100644
--- a/tcp_tests/fixtures/rally_fixtures.py
+++ b/tcp_tests/fixtures/rally_fixtures.py
@@ -18,13 +18,19 @@
 
 
 @pytest.fixture(scope='function')
-def rally(config, underlay):
+def rally(request, config, underlay):
     """Fixture that provides various actions for TCP
 
+    :param request: fixture provides pytest data
     :param config: fixture provides oslo.config
     :param underlay: fixture provides underlay manager
     :rtype: RallyManager
 
     For use in tests or fixtures to deploy a custom TCP
     """
-    return rallymanager.RallyManager(underlay, config.salt.salt_master_host)
+    with_rally = request.keywords.get('with_rally', None)
+    rally_node = "gtw01."
+    if with_rally:
+        rally_node = with_rally.kwargs.get("rally_node", "gtw01.")
+
+    return rallymanager.RallyManager(underlay, rally_node)