GitLab

Remove arguments from main.py.

Add "decontamination" prefix to ngrams arguments.

for some reason putting it in LM and having it be inherited breaks
everything. should try to figure this out at some point.

model_args should only be things that affect output of the model
therefore, stuff like batch size, device, etc shouldn't be in there

- Extract evaluator (still needs work to clean up)
- Add tests for evaluator
- Fix all the things that break on the new tests
- Misc cleanup

This should allow the user to only do the first few eval tasks.