Rename OS::Metering::Alarm to OS::Ceilometer::Alarm

The other resources are named by project so this is to
try and be more consistent.

There is a mapping to allow the original name to work.

Change-Id: If60cc577a5a770bdaada70c7eae1ae3fc1776056

etc/heat/environment.d/default.yaml

@@ -5,3 +5,4 @@ resource_registry:
     # Choose your implementation of AWS::CloudWatch::Alarm
     #"AWS::CloudWatch::Alarm": "file:///etc/heat/templates/AWS_CloudWatch_Alarm.yaml"
     "AWS::CloudWatch::Alarm": "OS::Heat::CWLiteAlarm"
+    "OS::Metering::Alarm": "OS::Ceilometer::Alarm"

etc/heat/templates/AWS_CloudWatch_Alarm.yaml

@@ -59,7 +59,7 @@ Mappings:
 
 Resources:
   __alarm__:
-    Type: OS::Metering::Alarm
+    Type: OS::Ceilometer::Alarm
     Properties:
       description:
         Ref: AlarmDescription

heat/engine/resources/ceilometer/alarm.py

@@ -130,5 +130,5 @@ class CeilometerAlarm(resource.Resource):
 
 def resource_mapping():
     return {
-        'OS::Metering::Alarm': CeilometerAlarm,
+        'OS::Ceilometer::Alarm': CeilometerAlarm,
     }

heat/tests/test_ceilometer_alarm.py

@@ -44,7 +44,7 @@ alarm_template = '''
   "Parameters" : {},
   "Resources" : {
     "MEMAlarmHigh": {
-     "Type": "OS::Metering::Alarm",
+     "Type": "OS::Ceilometer::Alarm",
      "Properties": {
         "description": "Scale-up if MEM > 50% for 1 minute",
         "counter_name": "MemoryUtilization",