Clean up/rationalize file types, suffixes, and calibration file types.

[dsavransky]

Right now we have several different indicators of what type of file a given pipeline (particularly an output reduced calibration file) is:

1) the file suffix ( "_wavecal", "_distor") 2) the FILETYPE keyword ("Wavelength Solution Cal File", "Distortion Calibration") 3) the calibration file type label used by the CalDB ("wavecal", "distor") 4) the CalFileType label, which used to be the 'Type' argument to each primitive prior to my work on #376. ("wavecal", "distorcal")

These are right now defined in various places all over the place and it's not very organized. The same text has to be entered in multiple places which can be error prone. There are cases like distortion where the CalFileType label doesn't match the suffix.

Here's my suggestion to clean things up:

• we should use one consistent set of file type labels/suffixes throughout the pipeline.
• the FILETYPE keyword should match this suffix, e.g. for wavecals we should have FILETYPE='wavecal' instead of FILETYPE='Wavelength Solution Cal File'
• create a new file in the config directory output_file_types.txt which gives the mapping between short filetype (suffix) and longer descriptions like 'Wavelength Solution Cal File' . Save_currdata can use this information to automatically populate the FILETYPE keyword's comment field. For back compatibility, the CalDB can use this table to translate long descriptive FILETYPEs into the shorter version.
• as suggested in #376, we/I can update __start_primitive to use the CalFileType argument from the XML files rather than having to hard code in each primitive the calfiletype variable as well as the CalFileType parameter.

[dsavransky]

Recovering rm journals for issue:

mperrin: This seems like more trouble than it would be worth at this point. Would have to re-reduce al the calibration files if we were to start cleaning up this legacy infrastructure code, even though I do still think it's a bit of a mess.