Add formats DMS/HMS and datetime

[rfrenchseti]

• Fixes #599. Fixes #1030
• Were any Django, import pipeline, table_schema, or dictionary files modified? Y
  • If YES:
  • Database used: New
  • All Django tests pass: Y
  • FLAKE8 run on modified code: Y
• Were any JavaScript or CSS files modified? Y
  • If YES:
  • JSHINT run on all affected files: NA
  • Tested on Chrome, Firefox, Safari, Edge, and iOS: N (Remember to test all browser sizes)
  • Tested for race conditions (with delayed API calls if applicable): NA

Description of changes:

• Change the way units are handled
• Add support for new datetime formats
• Add support for new latitude/longitude/hour_angle formats
• There is a new test suite for lib/opus_support.py. Just run "python opus_support.py" in the lib directory.
• You can run this version with the most recent test database, but you have to update the param_table first with "python main_opus_import.py --create-param".
• I slightly expanded the width of input fields so that a complete datetime string would fit in Linux Chrome. I have not been able to test on other browsers because I'm having trouble with BrowserStack, so testing would be greatly appreciated.
• The changes to the requirements are not caused by these changes, but by recent changes to pdsfile.

Known problems:

None.

[rfrenchseti]

• Date/time formats:
  • The "julian" module handles the following formats: YYYY-MM-DD[THH:MM:SS.sss], YYYY-DDD[THH:MM:SS.sss], JDxxxx, JEDxxxx, MJDxxxx, MJEDxxxx.
  • All of those formats are supported by just typing them raw into a date/time field, regardless of the currently selected units. In other words, if the current unit is "JD", you can still type "2010-01-01".
  • If you just type a number, it is interpreted according to the current unit selection.
  • Dates are limited to the years 1000-2999; anything outside of that range is considered an error
• RA/DEC/longitude/latitude formats:
  • Nd Nm Ns (degrees-minutes-seconds) or Nh Nm Ns (hours-minutes-seconds).
  • The last field (d/h, m, or s) can have fractions, but none of the earlier fields can. So "1.23d" and "1d 2.34m" are legal but "1.23d 10m" is not.
  • You can type a degrees string during "hours" units or vice versa and it will be interpreted properly.
  • You can type either a degrees or hours string during radians and it will be interpreted properly.
  • If you type a raw number, it will be interpreted according to the current units: degrees or DMS means degrees, hours or HMS means hours, radians mean radians.
• Numeric fields that support other types of units (duration, distance, resolution, etc.) can take an optional suffix to override the unit. So when "seconds" is selected, you can type "1" which means 1 second. Or you can type "1 day" or "1 hour" and it will convert for you. There are a wide range of things that will be understood.
• Spacing and capitalization shouldn't matter for any of the above as long as it doesn't introduce an ambiguity.

[rfrenchseti]

One more change: I increased the number of significant digits for wave number and wave number resolution.

[juzen2003]

UPDATE: after updating my local copy of pds-tools to have the latest version julian.py, JED & MJED work fine now.