`AttributeDict` typing and constructor updates

[pacrob]

AttributeDict and it's parent classes use Mapping[TKey, TValue] for typing, but in practice they often have multiple types in a single structure, at least in the values (strings, ints, hexbytes, etc.)

Consider changing the type, either by being more specific, or opening it to Any, as a user could theoretically turn any mapping into an AttributeDict.

Also, since an AttributeDict is expected to be a hashable datastructure, consider doing recursive tupleization/checking for unhashable types at the time of creation, instead of only when trying to hash it.

[fselmo]

I took a quick peek at this. The way it's currently set up allows the user to define what they want it to be. For example,

# this still works with `Any`
some_arg: AttributeDict[str, Any]

# but if we want to narrow the typing more, we can
some_arg: AttributeDict[bytes, bytes]

Unless I'm missing something, I think this is good the way it is. Thoughts?

[fselmo]

Also, since an AttributeDict is expected to be a hashable datastructure, consider doing recursive tupleization/checking for unhashable types at the time of creation, instead of only when trying to hash it.

I guess I didn't address this part but I feel like we shouldn't change the types that aren't assigned internally, especially if it is indeed declared at the type-hinting level. I'd rather only use it when hashing, as we currently do.

[pacrob]

Yep, no issue leaving as-is. I don't think I understood the creation process properly when I opened the issue.