Use Python names for classes, not names derived from CPython internals

[markshannon]

IMO, we should be using names derived from the the name of the class, not from the legacy C-API implementation.

There may be other cases, but the obvious examples are:

• h_BaseObjectType should be h_ObjectType.
• h_LongType should be h_IntType
• h_UnicodeType should be h_StrType
• Other uses of Unicode.