Reduce requirements

[AstraLuma]

IMHO, requirements.txt should only be what you directly depend on. If you want more extensive version pinning (freezing, locking), something like a constraints file should be used.

(pipfile/pipenv can also be used, but I've found deploying with pipenv to be challenging in the past.)

More information:

• https://stackoverflow.com/questions/34645821/pip-constraints-files

[rowanlupton]

i believe that i have just pruned this down (i actually went through the code and added things i was directly importing instead of going through requirements and being like "uhhh i think i directly need that?") in my last commit