There are `print()` usages where using `logger` would be better

[anthonyduong9]

There are print() usages where using logger would be better, so clients of this library can configure logging verbosity and track the severity of events. Also, this library configures logging but shouldn't, so clients can configure logging verbosity as they wish. Last, there are print() usages in tests, but I think they should be deleted.

[anthonyduong9]

I'm thinking we should

• delete the print() lines in tests
• replace the print() lines with logger usages, everywhere except __main__.py, neighbours.py, and load_sparsify.py, which seem like CLI code, and result_analysis.py, because of the description in Log count of features excluded from explanation (e.g. for being dead) #96
• move the logic in logger.py (to configure logging) to __main__.py.

I'm also wondering if we should move __main__.py from delphi/delphi to delphi, i.e. out of the package/module.

If this is ok, I can start working on this.

[SrGonao]

I think the prints in test stayed by mistake. Everything else should be fine.

I'm also wondering if we should move main.py from delphi/delphi to delphi, i.e. out of the package/module.

We have it like that for sparsify. I'm not sure why you would have one and not the other, what's your take?

[anthonyduong9]

@SrGonao in that case, never mind, it's not a big deal.