…nt with OAS conformance suite

Add preliminary support for example validation in OpenAPI3 and Swagger.

…nt with OAS conformance suite

This adds normalization of schemas present in Swagger/OpenAPI. When an example is detected, the object being it's schema is passed through the normalizer to be transformed into a single object where all references are resolved.
This also extends the validation preferences for Swagger/OpenAPI to add an option to enable example validation. This option is set to false by default.

…nt with OAS conformance suite

Add extension point.

…nt with OAS conformance suite

Removing example validators as they will be implemented as extensions inside API Studio.
Also modified the preference pages and initialisers so that that validation extensions can add and initialise their own values.

…nt with OAS conformance suite

KZOE and API Studio both provide their own version of json-schema-validator and this is causing an exception to be thrown when a validator extension is created in API Studio and called from KZOE. To avoid this issue, all call to json-schema-validator should be done through the KZOE class `JsonSchemaValidator` that will execute the validation without exposing any json-schema-validator API.

…nt with OAS conformance suite

Add the extension point `com.reprezen.swagedit.preferences` that allow clients to provide their own preferences to KaiZen editors.

…nt with OAS conformance suite

Add missing change in plugin.xml

…nt with OAS conformance suite

Fix wrong ID.