Allow user created @PATCH, @GET ...etc annotations

[ed0906]

Solution to defect: #1643.

Currently Javax does not support the PATCH annotation so some users have created their own in the form below to avoid them coupling their code to Swaggers io.swagger.jaxrs.PATCH:

@Target({ElementType.METHOD})
@Retention(RetentionPolicy.RUNTIME)
@HttpMethod("PATCH")
public @interface PATCH{ 
}

Which is picked up by Jersey but not by Swagger. This change makes swagger check through all resource method annotations to find the HttpMethod like above.

[webron]

@frantuma - can you review this please?

[frantuma]

@webron looks ok, it adds additional option as source of http verb for operation.