Feature suggestion: extract command

[jtmiclat]

Hi! A processing I found useful when using geoparquet files is creating subsets of data with either using bbox or excluding/selecting columns.

rough suggested implementation

gpq extract -bbox=120,10.1,121.4,11 -geom_col=geometry -exclude_cols=value,label source.geoparquet target.geoparquet

I can work on the implementation of this in the upcoming weeks but would like to know if others would find this useful!