Keep all the titles of a Wikipedia internal link.

Accessing children directly might give a NullPointerException. It would safer if you created a `InternalLinkNode.getLabel` method that defaults to WikiTitle.decoded.

Then this would simplified to something like `internalLinkNode.getLabel.equalsIgnoreCase(internalLinkNode.destination.decoded)`

btw, haven't tested it but is `StringParser` necessary?