More Control Over the GeoTiff Saved in saved_stitch

[jbouffard]

The save_stitched method currently saves the GeoTiff with the default settings https://github.com/locationtech-labs/geopyspark/blob/master/geopyspark-backend/geotrellis/src/main/scala/geopyspark/geotrellis/SpatialTiledRasterLayer.scala#L218

It'd be nice to have more control over the GeoTiff that is saved. This could be done using similar parameters used in to_geotiff_rdd. https://github.com/locationtech-labs/geopyspark/blob/master/geopyspark/geotrellis/layer.py#L391