Pandeia v1.4.2 update

[ariedel]

The pandeia v1.4.2 update (https://github.com/spacetelescope/pandeia_data/pull/439) only involves a new datafile.

The notebook updates:

• Pandeia-WFIRST: Has all the new filter and disperser names, and some cleanup, and sections for using the new sersic and power law source profiles. Also has a new Results section printing out ALL the results.
• Pandeia-WFIRST_GUI: Fixed so that it reads the GUI out of the nbutils2.py file in this repo. That GUI has been updated so that sersic_scale and power law profiles work correctly, as do changing dispersers (not noticed before we had two to choose from). Additional cosmetic updates: The distracting grid on the 2D plots is gone, a scale bar has been added to the plots, and there's a new Results pane.

[ariedel]

Played with the binder, it all seems to work!