Retrive webp image metadata

[KalhariL]

Webp images can contain useful EXIF metadata. Webp reader is not retrieving any metadata and the method is not implemented. This is a rather useful feature and appreciate if you could implement it.

com.luciad.imageio.webp.WebPReader

@OverRide
public IIOMetadata getImageMetadata( int imageIndex ) throws IOException {
return null;
}