get NLCD values and nearby OSM features for Alaska air study

[turbomam]

actually, most of these files probably belong in a different repo

could be generalized to any input file, as long as the sample_name, lat, and long column names are specified.

Note that the most recent NLCD data for Alaska seems to be from 2016, when they used the ERDAS Imagine format (.img). This format expects the following file types the same location:

• .img file: The main raster data.
• .ige file: An auxiliary file for large datasets, handling image pyramids or extensions.
• .xml file: Metadata about the dataset.

Newer NLCD datasets use GeoTIFF

[turbomam]

move all of this to the external metadata awareness repo