Extract stack of netCDF files to CSV

[brendan-ward]

Use case:

• One netCDF file contains the IDs of reporting units (digitized from polygons).
• Extract from a large stack of netCDF files that match exactly in terms of spatial footprint

Output should be CSV, with first column as reporting unit ID, and one column per netCDF file.

Allow control of precision.

Will need to build in chunking for the data extraction to avoid running out of memory, but tune so that there isn't a lot of I/O churn.

[brendan-ward]

Alternatively, this could be a singular operation: input ID file and data file, and return a CSV of those pairs by pixel.

Then use a post-processing step (e.g., using pandas) to join those together.