Add synchronous blocking API to Write time-series data into InfluxDB 2.0

Useful for simple use case of client:

- simple IOT device
- Apache NiFi - buffering and grouping is provide by NiFi - https://github.com/influxdata/nifi-influxdb-bundle/issues/23

