Function enumeration

enumeration<E>(enumObj: object, decoderName: string): Decoder<E>
Decoder for enumeration values.
Type Parameters
- E
Parameters
- enumObj: object
  The enum object to use for decoding. Must not be a const enum.
- decoderName: string
  How to display the name of the object being decoded in errors.
Returns Decoder<E>
A decoder that validates and returns enum values
Example
```
enum Color {
  Red = 'red',
  Blue = 'blue'
}

const colorDecoder = JsonDecoder.enumeration(Color, 'Color');
colorDecoder.decode('red'); // Ok<Color>({value: Color.Red})
colorDecoder.decode('green'); // Err({error: '<Color> decoder failed at value "green" which is not in the enum'})
```