Data store sync example for experimentation

[slawr]

WIP code in branch: https://github.com/slawr/cdsp/tree/experimental-iotdb-sync
Actual example: https://github.com/slawr/cdsp/tree/experimental-iotdb-sync/examples/data-store-sync-iotdb

[slawr]

The example provides a simple two data store deployment to allow sync experiments. For example, manually using the IoTDB CLI.

Currently CDSP uses IoTDB v1.3.3. The documentation states it supports two sync modes, batch and real-time.

My initial experiments simply inserting data into one DB and observing when it appeared in the other showed a several minute delay when using the real-time mode. There were online reports of sync issues fixed in IoTDB v1.3.4 so that was a possible cause/solution.

During a sync meeting between the IoTDB community and CDSP maintainers the IoTDB community informed that real-time was not supported in the OSS IoTDB. For that the enterprise edition from Timecho was required. They considered that setting real-time should not be possible. The next step on CDSP side is to check locally and report back to the IoTDB community.