Added 'k8s_deployed' fixture

Created a separate fixture for Kubernetes deployment.
Modified existing k8s related fixtures / tests so they
use it now and updated templates with k8s environments.

Also this patch includes few minor changes:

 * removed unused fixture 'deploy_openstack' which
   was a full copy of 'openstack_deployed' fixture;
 * removed unused modules imports;
 * fixed typos and docstrings.

Change-Id: Ic35551f3e52913cede753b92e7d5a81f54570b01
Reviewed-on: https://review.gerrithub.io/365234
Reviewed-by: <vrovachev@mirantis.com>
Reviewed-by: Dennis Dmitriev <dis.xcom@gmail.com>
Tested-by: Tatyanka Leontovich <tleontovich@mirantis.com>
diff --git a/tcp_tests/managers/saltmanager.py b/tcp_tests/managers/saltmanager.py
index 304ff75..f8a3fd8 100644
--- a/tcp_tests/managers/saltmanager.py
+++ b/tcp_tests/managers/saltmanager.py
@@ -11,7 +11,6 @@
 #    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 #    License for the specific language governing permissions and limitations
 #    under the License.
-# import time
 
 from collections import defaultdict
 
@@ -151,3 +150,7 @@
             r = self.run_state(tgt=tgt, state=s, args=args, kwargs=kwargs)
             rets.append(r)
         return rets
+
+    def get_pillar(self, tgt, pillar):
+        result = self.local(tgt=tgt, fun='pillar.get', args=pillar)
+        return result['return']