Uniform Airflow migration strategy implementation

This is one of the algorithm of Intel thermal POC.
It's based on the Airflow of hypervisors.

Change-Id: I48bbab75b20129d85b1fb15ede823474546fe399
blueprint: uniform-airflow-migration-strategy

watcher/decision_engine/goal/goals.py

@@ -129,3 +129,23 @@ class WorkloadBalancing(base.Goal):
     def get_efficacy_specification(cls):
         """The efficacy spec for the current goal"""
         return specs.Unclassified()
+
+
+class AirflowOptimization(base.Goal):
+
+    @classmethod
+    def get_name(cls):
+        return "airflow optimization"
+
+    @classmethod
+    def get_display_name(cls):
+        return _("Airflow optimization")
+
+    @classmethod
+    def get_translatable_display_name(cls):
+        return "Airflow optimization"
+
+    @classmethod
+    def get_efficacy_specification(cls):
+        """The efficacy spec for the current goal"""
+        return specs.Unclassified()