Convert IByteConverter from an interface to static implementation

IByteConverter doesn't really represent methods that will ever have varied implementations. The way you read an integer in big-endian by order from an array of bytes is always the same.

As such, we can gain performance improvements by using static methods rather than an interface to access the implementation. This is a big advantage given how frequently these methods are used.

1. This will allow the JIT compiler to inline the methods where reasonable
2. When they aren't inlined, it will above virtual method table lookups to execute the call
3. It won't be necessary to pass references to IByteConverter around between classes/methods