namespaces+discussion

I want to distinguish a strong form of namespaces and a more general one that can support name related features inside of a deck. The strong form implies that all the parts of all names within the namespace, but this will not be true of this weaker sense. In this weaker sense, any cardname is a namespace for all cards below it, and recursively any namespaces it contains, and we can test if a card is in a namespace, including or excluding any subspaces stacked below it.