[keycloak-dev] new generic component storage

I've implemented a new generic component storage, api, REST API, and admin console support. Classes/interfaces are in server-spi org.keycloak.component package and created via methods in RealmModel. It is basically a more generic form of mapper models, UserFederationModel, etc. Components describe themselves and can be generically rendered by the admin console. The storage model is meant to support nested subcomponents (i.e. UserFederationModel and UserFederationMappers). Config now supports a MultivaluedHashmap instead of a flat Map to support list storage. There is a common REST API under the realm that should be usable for all component types. The UserStorage SPI uses this new SPI from top to bottom. We should consider whether we want to migrate other component types to this new model. When you create components to store, you specify a parentId (i.e. Realm, Client, a parent component), a provider type, a provider id, and config. For export, the json model will contain components under Realm and Client where the perspective parentId is Realm and Client. I still want to make this as human consumable as possible so that these components can be defined by humans in json. Bill