…classes to provide compatibility with .Net Standard 2.0

…in .Net Framework 2.0

…Split()

… same method siganture.

…to maintain backwards compatibility.

…is not defined for .Net Standard 2.0.

… don't break .Net 6 async stream behaviour.

…orwards compatibility with the .Net 6 codebase.

… package references for .Net Standard 2. Exclude LaserCatEyes for .Net Standard 2 as it only supports .Net 6 or later.

…andard 2. Downgrade package references and add new package references so it will compile and run in both environments.

Add support for .Net Standard 2.0