Move SecurityScheme annotation to model mapping to core

[bgK]

This moves the SecurityParser class responsible for populating SecurityScheme models from SecurityScheme annotations to the core module. The move allows using it without taking a dependency on JAX-RS and to use it for building integrations for other technologies.

I'm opening this very simple pull request as a probe. Is moving the code for mapping annotations to models out of the jaxrs module desirable for the project? Some related code is already in the AnnotationsUtils class in the core module.