CacheValueError name is confusing #23
Description
Currently we raise a CacheValueError for any INVALID_ARGUMENT grpc status codes. For example, this is raised if create_cache is called with an empty string.
This name was derived from ValueError in Python, but the naming of it makes it seem like something is wrong with the value being cached.
It might be better to rename this to something like InvalidArgumentError so it's clear that it's not just for cache values.