fix issue 5 & 6

[ruby109]

There is no need to use PrettyRawRepresentable unless you want to specify the type. Using extension can do the same thing and pass tests.
If you still want to use PrettyRawRepresentable, you can write it like this

public protocol PrettyRawRepresentable: RawRepresentable{

}

public extension PrettyRawRepresentable where RawValue == String {
    var prettyRawValue: String {
        let paths = String(reflecting: self).splitWithoutFirst()
        if String(paths.last ?? "") != rawValue {
            return rawValue
        }
        return paths.joined(separator: "_")
    }
}

public extension PrettyRawRepresentable {
    var prettyRawValue: String {
        return String(reflecting: self).splitWithoutFirst().joined(separator: "_")
    }
}

In issue 6, instead of using rawValue, you can use prettyRawValue to get the correct Info