Consider supporting fully-specified schemata

[eevee]

I originally thought this would be better served by combining Camel with another library like Colander, but maybe it's reasonable to include:

21:27 < _habnabit> eevee, if you made your library handle defining schemata, i'd probably use it 21:29 < eevee> _habnabit: i don't think it would actually be /that/ big a leap to have schemata... be more specific about what you promise to spit out when dumping and you're most of the way there