Add DescribeAlarms
Fix listMetrics to return NextToken
Add a test case for GetMetricStatistics
Add DescribeAlarmsForMetric
Add "Unit" property to MetricAlarmType
Add PutMetricAlarm
Fix result parsing
Add DeleteAlarms
Add DescribeAlarmHistory
Add EnableAlarmActions
Add DisableAlarmActions
Add SetAlarmState
Add PutMetricData
Merge remote-tracking branch 'origin/cloudwatch'