Implement Loguru for better logging

[smoia]

So far we're adopting basic logging - 95% of the time that's ok, but for instance the logs are not catching errors, which is annoying for bugfixes.

Loguru might offer a solution, at a very small dependency cost - especially if not on Windows (otherwise two small dependencies more to deal with their terminal).

I think it'd be neat to implement it!

[maestroque]

Existing draft PR: #53

It should entail more or less the changes done in physiopy/peakdet#62, including the logger utility functions.

A point of discussion would be if these utility functions could be transferred in physutils, since they are to be used universally (probably) in the configuration of loguru.