More candy from Hush

* We're avoiding mutability a lot in Hush, which would explain some of
  the seemingly trivial categories on dictionaries.

* The usefulness of each of these in a generic sense is open to debate
  if the reviewer considers these to be too specific to Hush.
Hmmm. Ok. This looks fine. I get uncomfortable with if-else-if-else-if thats doing type checks. This sort of code can always be replaced with polymorphism.