K8s Schema Matcher (#307)

* Implement K8sSchemaMatcher class

* Apply property-name-based heuristic on ranking matched schema

* Improve schema matching heuristic

- Observe property names used for each k8s schemas in k8s schema spec
  and use them to improve ranking of matched schemas

* Fix code style and add documentation

* Add test cases for K8sSchemaMatcher

- Added kafka_crd to test_data/
- Added test case generation code
- Partially fixed pylint warnings in test code

* Match descendants of matched schemas

* Rename K8s dict and list schema class

* Use YAML for dumped schema files

* Fix and improve type hints