Also allow 'dods://' (opendap)
[1589]
Logic should be Am-I-part-of-a-VIIRS-formula (not just an RGB) [1540]
Fix PEP257 warnings in imageFilters.py. [1780]

Also made some indentation more consistent.
Fix PEP257 warnings in hydra.py and colorutils.py.

[1780]
Fix PEP257 warnings in interactive.py. [1780]