v1.2.1

A couple of nice updates in this one:

• Added a new AsValue() extension method on objects implementing IEquatable<T>
  • This makes it simple to fold in existing types which implement IEquatable, like System.Drawing.Color, for example.
• Now with the AsValue extension this works seamlessly with new C# 9 record types.
  • This goes both ways! Both a record exposing a Value and a Value exposing a record are equal!
• Cleaned up the root namespace a bit so that the specific derivative types are not there to clutter the namespace.