Finished VIIRS crefl files. Requires VIIRS frontend to work. Updated
VIIRS frontend to allow for each variable loading from a navigation
file. Added rescaling for the CREFL bands at the 4 main possible data
sizes. Added sharpening method/module. Added a simple crefl glue script
that has a special case for making the true color image.
Fixed python ll2cr bug when the frontend doesn't provide bounding
coordinates and is being remapped to a static grid.
Added units to all PROJ.4 grid definitions that need it and added an
equidistant cylindrical projection (eqc_fit).