i18n - Make string translatable

Since internationalization should be enabled in Watcher, this
patchset refactors the Watcher codebase to wrap previously
untranslatable strings with i18n translation functions so we can
import them for translation into the .pot template file.

Partially Implements: blueprint support-translation
Change-Id: I425967a60b5a7957f753894e5d2ba0d2c5009d1d

watcher/decision_engine/rpcapi.py

@@ -28,7 +28,6 @@ from watcher.common import utils
 from watcher.decision_engine.event.consumer_factory import EventConsumerFactory
 from watcher.decision_engine.manager import decision_engine_opt_group
 from watcher.decision_engine.manager import WATCHER_DECISION_ENGINE_OPTS
-
 from watcher.decision_engine.messaging.events import Events
 
 LOG = log.getLogger(__name__)
@@ -82,5 +81,5 @@ class DecisionEngineAPI(MessagingCore):
             event_consumer = EventConsumerFactory.factory(event_type)
             event_consumer.execute(request_id, self.context, data)
         except Exception as e:
-            LOG.error("evt %s" % e.message)
-            raise e
+            LOG.exception(e)
+            raise