Add color ramp and color table to raster exports

[CameronBodine]

• [x] Add color table to substrate prediction, see: https://gis.stackexchange.com/questions/325615/store-geotiff-with-color-table-python
• [x] Add color ramp to sonograms, see: https://gis.stackexchange.com/questions/354650/gdal-colorramp-for-float-based-values

[CameronBodine]

Added Doodler color ramp to substrate maps.