feat: Added integration with the built-in logging package

[dylan-robins]

Closes: #49

This PR integrates the built-in logging package, as listed in the Cleo 3.0 writeup (#415 ). Implementation is of course subject to change, but I thought I'd get the ball rolling :)

Here's what I did:

• Added an OutputHandler class, allowing logging to emit LogRecords to a cleo.io.outputs.output.Output
• Added a method to cleo.application.Application which attaches an OutputHandler to the root logger, and configures it to have a log level that is coherent with Cleo's one.
• Added unit tests ensuring all this works as expected.

Here are some open points that I know we need to discuss:

• How should we map logging's log levels to Cleo's verbosity levels? Current implementation is as follows:
  • Quiet: CRITICAL (but nothing gets printed anyway so whatever)
  • Normal: WARNING
  • Verbose: INFO
  • Very verbose: DEBUG
  • Debug: DEBUG
• Formatting:
  • Should the stuff coming from the logging handler have some sort of prefix or something to distinguish them from what is coming directly from output.write_line()?
  • The formatter styles for error, warning, info and debug need to be defined.

[Secrus]

Hey, first of all, thank you for your contribution. A couple of things to start with:

1. Logging integration shouldn't be automatic. We should only provide a logging.Handler class (CleoHandler maybe?) and leave the rest to the user.
2. I believe we can have a deeper integration and provide more from Cleo than just wrapping io.write into a logging handler. See what Rich does in their logging module. It won't be 1:1, but it should give you some ideas.
3. The code should be moved to cleo.logging module.

[dylan-robins]

Thanks for the feedback, I'll look into everything you said and update my branch accordingly. I'll let you know when I have something worth reviewing!