Naming geotargets gdal raster options

[njtierney]

Breaking this out of #19

Naming things is always a bit tricky, but following on from @Aariq 's suggestion on renaming some of the env vars, current thoughts are:

GEOTARGETS_GDAL_RASTER_DRIVER_NAME -- > GEOTARGETS_GDAL_RASTER_DRIVER

It's a small change but I think it's worthwhile to reduce typing where practical. On the GDAL website they are called "Raster drivers" too, so there's that?

[brownag]

Totally agree with dropping "_NAME" from the option name, that is a great suggestion

I also agree with your point RE: "CREATION_OPTIONS" (#19 (comment)).

At a minimum we need to distinguish between options used to write/create a datasource vs. those used to read/open them.

[njtierney]

closed in #30