Flat field reference file updates

[bhilbert4]

Karl still has not delivered the F070W flat (and maybe also the F090W) flat. He was having trouble removing all of the illumination pattern effects and wanted to keep working on it.

Also, a check of the other flat field reference files in CRDS show that the error and DQ extensions that Karl provided have been zeroed out. Most likely this happened when converting Karl's files to SSB format and the extensions were never checked. These files will have to be remade at some point.

Deadline for everything is 31 January 2018.