Add more configuration options to createTree function and top-level component

[McTano]

I'm going to change the signature of the createTree function to take an options object so we can have named parameters instead of relying on argument order. It might be trickier to make it work in the filter on the carnap side, but it'll make it much easier to add options later.

• option to show debug info (JSONView) or not (default=false)
• configure label to use instead of 'Struct' rule (default='Struct')