Documentation and usage of capirca.lib.naming.Naming

If I understand the library correctly, capirca.lib.naming.Naming is used to parse the pol, net, and svc files. There was an effort to add yaml to add it as an alternative (#73 ), however that was ultimately not considered. I understand the maintainers not wanting to add additional features, but I am proposing a slightly different approach to the same problem. Can we instead.

* Create an abstract class (may or may not be an actual abc), called `AbstractNaming`, or similar
* This class would be inherited from any parser built, such a `Naming`
* This class would document the expected api/signature/interface for any parsing class that inherits from it, ideally with type hinting
* Split parsing tests up between inputs and outputs, so any externally built parser can inherit from the same tests

This way, other libraries that inherit from caprica can translate from their models more easily, without increasing the maintainability of the project.