v0.3.0

• Breaking: Throw if type or items fields in a schema object are arrays
  • OpenAPI Schema Objects don't allow these fields to be arrays unlike JSON Schema
• Support references to Components Object everywhere that OpenAPI Specification allows
  • Additional places where references are allowed: inside Schema Objects, Request Body Objects and Header Objects
• Support Schema Objects that contain items and properties fields
• Better support (resolve references and support nullable) for additional schema fields that contain schemas: allOf, anyOf, oneOf, not and additionalProperties