tempest: Allow to not run deprecated API tests

This change introduces the tempest option
[telemetry]/deprecated_api_enabled to not run
tests against the old API.

Change-Id: I66189111d795b88625fb4d41f853c848decccc05
diff --git a/ceilometer/tests/tempest/api/base.py b/ceilometer/tests/tempest/api/base.py
index 03e9acd..5239fb9 100644
--- a/ceilometer/tests/tempest/api/base.py
+++ b/ceilometer/tests/tempest/api/base.py
@@ -47,8 +47,9 @@
     @classmethod
     def skip_checks(cls):
         super(BaseTelemetryTest, cls).skip_checks()
-        if not CONF.service_available.ceilometer:
-            raise cls.skipException("Ceilometer support is required")
+        if (not CONF.service_available.ceilometer or
+                not CONF.telemetry.deprecated_api_enabled):
+            raise cls.skipException("Ceilometer API support is required")
 
     @classmethod
     def setup_credentials(cls):