terrautils/imagefile.py: add EPSG parameter and update doc

[Chris-Schnaufer]

Tags: EPSG, Coordinate System, Spatial Reference
Tags: EPSG, Coordinate System, Spatial Reference

Description

image_get_geobounds() and polygon_to_tuples() assume a coordinate system. This could cause problems when dealing with different coordinate systems.

Details

• Add an EPSG parameter to image_get_geobounds() that defaults to 4326.
• Document polygon_to_tuples() to indicate no conversion happens and to use polygon_to_tuples_transform() if coordinate systems are a concern

Completion Criteria

• image_get_geobounds: an EPSG parameter is added that defaults to 4326
• image_get_geobounds: a conversion is done for non-EPSG:4326 values
• image_get_geobounds: correctly converted values are returned
• polygon_to_tuples: documentation is updated

References:
https://app.zenhub.com/workspaces/ua-ag-data-science-5a57a3198339f11ba1c85775/issues/terraref/drone-pipeline/37
https://app.zenhub.com/workspaces/ua-ag-data-science-5a57a3198339f11ba1c85775/issues/terraref/drone-pipeline/55