Remove Ocean Color datasets

[frankinspace]

Related to #14

An alternative approach to reducing costs could be to remove processing of the ocean color datasets.

@edshred2000 mentioned that ocean color is used to derive experimental variables in the output datasets. So removing ocean color would mean we lose those variables, but the SST variables (which are of higher value) would not be affected.

[nikki-t]

Work tasks to complete to remove ocean color variables from MODIS Aqua/Terra datasets:

1. Remove OC file downloads from download list creator component.
2. Remove OC variables chlorophyl_A and K490 from combiner and processor components.
3. Modifications have been tested in SIT and UAT.
4. Modifications have been deployed to OPS.