Spelling and grammar changes.

[TimothyMakkison]

Really cool library, nice to see modern allocation free C# code. 🚀

• Minor spelling corrections.
• Edited some pargraphs.
• Tried to avoid changing the formatting or the information.
• This isn't exhaustive, there are still some areas that could do with a rewrite.

I've noticed a lot of typos/spelling mistakes in the code base, but haven't fixed any in case I break something. Have you considered using Visual Studio spell checker or cSpell for vscode, they would probably catch most of your typos.