Add Spring Security OAuth2 support to Spring Boot CLI

* Triggered from either @EnableAuthorizationServer or @EnableResourceServer
* Needs to have @EnableGlobalMethodSecurity to allow picking the annotation model.
* By default, comes with import support for @PreAuthorize, @PreFilter, @PostAuthorize, and @PostFilter via a single start import
* Also need import support for the enable annotations mentioned above.
* Added extra test case and sample (oauth2.groovy)