Fix #231: tokens.xml no longer overwritten by cards.xml.

Apparently the fix was exactly as simple as I thought it wasn't. @Psithief does this fix the issue?
@Daenyth I only used `tokens` because that's what it used to be called, although I agree it's not very descriptive. `includeTokens` may not be the best name because we include *only* tokens if `includeTokens` is true, not in addition to the other cards. I'm not sure what else to name it, any other naming suggestions? Or I can just leave a comment.