Process timestamps series into VSRI indexes

[cjrolo]

Is your feature request related to a problem? Please describe.

Currently, although it is part of our paper and research, VSRI indexes are not supported in the compressor. They should be added.

Describe the solution you'd like

Add VSRI support to the ATSC compressor. Both at compression time and decompression.

Additional Context

VSRI is also a particularly good method of compressing time series, time data. But currently ATSC compresses a time series without any information about... time.
Adding VSRI support would allow the time information to be supported.

Also, following issue 129, most CSV files would probably have a timeseries with time included.
So, once issue 129 is supported, it seems natural that we compress the time information too.

[cjrolo]

Working in https://github.com/instaclustr/atsc/tree/vsri-generator