Add more models, code cleanup, better configurability

What's Changed

• Add missing models / Code cleanup by @duckdoom4 in https://github.com/Kav-K/GPT3Discord/pull/120
• Fix spelling mistakes by @duckdoom4 in https://github.com/Kav-K/GPT3Discord/pull/119

New Contributors

• @duckdoom4 made their first contribution in https://github.com/Kav-K/GPT3Discord/pull/120

Full Changelog: Kav-K/GPT3Discord@v8.6...v8.7