Split metapackage into various subpackages

[MaddyGuthridge]

This will allow us to reduce disk usage in limited environments such as the exam environment.

Core dependencies:

• Flask
• PyHTML
• requests
• types-requests
• Colorama
• types-colorama

Suggested groups

• Testing

  • Pytest
  • Jestspectation
  • Subtask
  • Mypy

• Jupyter

  • ipykernel
  • pandas
  • numpy

• Extras

  • pillow

• All (includes all of the above)

That way we can get students to install comp1010[all] but in the exam we can just provide comp1010[testing]