Artifact names, artifact identification scroll

[Gerhazo]

There's unused name generation code that artifacts have that grants all of them neat internal names, which are influenced by the type of artifact they are(eldritch artifacts have sinister-sounding names, for instance). This patch causes that internal name to reveal itself when an artifact is activated. Additionally, it introduces a new item in Vurdalak's inventory, a scroll of identify that can be used on artifacts to reveal their name, type of the artifact and the activation method, when applicable.