Influxdb java client sends null to influxdb

When I use POJO with the client, null values are not filtered out before sending to the DB. Since influxDB does not accept null fields and tags, error is thrown and data is lost.

This is case when I use InfluDBMapper and use save() or if I use addFieldsFromPOJO() function to create a Builder.
Either ways null values are propagated in both tags and fields. This almost renders the POJO useless.

Is there any workaround here?

For anyone coming across this issue: I submitted a PR - and it is merged in the master branch