Increased Clarity For Help Command Signatures

[mistcurve]

Currently after calling .help log the signature at the top is displayed as

.log

My suggestion is to include function arguments in brackets to indicate order of the arguments, or otherwise clarifying the format if tagged arguments are added

.log [words] [genre]

[Swiddis]

This might need a custom help command, I'm not sure if this is configurable within the default discord.py help setup. I also was wrestling a bit with the help for args under buy to see if I could make it more useful but haven't had much luck, so this isn't the only issue with the default help either.