[EAGLE-872] Transform counter metric to rate metric

[r7raul1984]

• Add transform bolt using counterToRateFunction in HadoopMetricMonitorApp's storm topology.

https://issues.apache.org/jira/browse/EAGLE-872

[haoch]

@r7raul1984 would you convert all counter metric to rate?

[r7raul1984]

@haoch If metric name endswith "count" , it will be converted to rate.

[haoch]

@r7raul1984 how do you think expose CountMetricFilter as a parameter to choose which metric to convert as count, and the current hard-code behavior should only be some kind of default implementation?

@FunctionInterface
interface  CountMetricFilter extends Function<Map, Boolean>

DefaultCountMetricFilter = (metric) -> metric["metric"].endsWith("*.count")

[haoch]

LGTM

[r7raul1984]

@haoch Thanks. I will merge.