Update requirements.txt file for all packages except Django

[rfrenchseti]

• Fixes #1209
• Were any Django, import pipeline, table_schema, or dictionary files modified? Y
  • If YES:
  • Database used: opus3_test_211123
  • All Django tests pass: Y
  • FLAKE8 run on modified code: Y
• Were any JavaScript or CSS files modified? N
  • If YES:
  • JSHINT run on all affected files: Y/NA
  • Tested on Chrome, Firefox, Safari, Edge, and iOS: Y/NA (Remember to test all browser sizes)
  • Tested for race conditions (with delayed API calls if applicable): Y/NA

Description of changes:

Renamed requirements-python3.txt to requirements.txt. Removed special Mac and Windows versions.

Known problems:

Django packages will need to be updated separately.