Support population size calculation in missing sinks #135
Description
The HttpPostSink supports publishing the metrics samples_sent and samples_dropped if the population size of samples in calculated in serialize method of the implementing class. Currently only the KairosDBSink makes this calculation while the other sinks that extend HttpPostSink leave it empty (it is an Optional) so these metrics are not published for these sinks. In order to support the metrics samples_sent and samples_dropped in all sinks, the serialize method must be implemented to calculate the population size of each byte[] chunks for the following sinks:
- SignalFxSink
- MonitordSink
- KMonDSink
- InfluxDBSink
- DataDogSink