Allow "engine debugging" to be enabled.

[folkertvanheusden]

Type of pull request:

• [ ] Bug fix
• [X] Feature
• [ ] Other

Description:

This change allows a developer to enable UCI/XBoard protocol debugging to be enabled. This helps debugging communication problems between lichess-bot and certain chess engines.

Related Issues:

[Reference any related issues that this pull request addresses or closes. Use the syntax Closes #issue_number to automatically close the linked issue upon merging.]

Checklist:

• [X] I have read and followed the contribution guidelines.
• [X] I have added necessary documentation (if applicable).
• [X] The changes pass all existing tests.

Screenshots/logs (if applicable):

[MarkZH]

Good idea. Just fix the errors in the tests. Namely, the Stockfish.__init__() method in test_bot/homemade.py (and all the classes Stockfish inherits from) needs to be changed to take a debug paraemeter.

[folkertvanheusden]

@MarkZH hi, I made the change. Could not find any other class that Stockfish inherits from. But pytest with the latest fix runs fine and it hangs without the fix so my guess is that it is now good?

[MarkZH]

I forgot to mention, please add documentation to the config wiki page: wiki\Configure-lichess-bot.md

[folkertvanheusden]

I forgot to mention, please add documentation to the config wiki page: wiki\Configure-lichess-bot.md

Done!

[AttackingOrDefending]

Can you fix the mypy errors?