Refactored existing tempest API tests

We must set up Tempest for Watcher
(http://docs.openstack.org/developer/tempest/configuration.html)
to run integration tests inside devstack environment.

This patchset is a refactoring of the stale Tempest tests to now
use the latest Tempest coding standards (like using plugins and
credentials factory).

This commit will have an effect on the doc as we need to integrate
Tempest in the Watcher documentation.

DocImpact
Partially Implements: blueprint tempest-basic-set-up
Change-Id: I7600ff8a28d524b56c7dd4903ac4d203634ae412

watcher_tempest_plugin/plugin.py

@@ -0,0 +1,36 @@
+# Licensed under the Apache License, Version 2.0 (the "License"); you may
+# not use this file except in compliance with the License. You may obtain
+# a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# 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 os
+
+from tempest import config
+from tempest.test_discover import plugins
+
+from watcher_tempest_plugin import config as watcher_config
+
+
+class WatcherTempestPlugin(plugins.TempestPlugin):
+    def load_tests(self):
+        base_path = os.path.split(os.path.dirname(
+            os.path.abspath(__file__)))[0]
+        test_dir = "watcher_tempest_plugin/tests"
+        full_test_dir = os.path.join(base_path, test_dir)
+        return full_test_dir, base_path
+
+    def register_opts(self, conf):
+        config.register_opt_group(
+            conf, watcher_config.service_available_group,
+            watcher_config.ServiceAvailableGroup)
+
+    def get_opt_lists(self):
+        return []