The logic for both of these has been corrected; neither will try to
handle reserved or preexisting attributes as though they should be part
of their dicts.
These can still be set manually, but it makes things much safer.
New attributes have to come from the class or local __dict__ modifications.
Redid some of the logic behind AttrDict. It now raises AttributeError
when necessary, instead of giving the incorrect KeyError response.
This has restored compatibility with copy.deepcopy().
This code should split things more neatly than the current Pesterchum
code, thus fixing a number of irritating bugs. Ideally, when finished,
it will be easier and cleaner to work with as well.
