Minor refactoring

Rename AnnotatedDataFetcherConfigurer -> AnnotatedControllerConfigurer,
since handler methods are now not only data fetchers but also
batch loaders.

Move DataFetcherHandlerMethod and BatchLoaderHandlerMethod into the
support package next to AnnotatedControllerConfigurer where they're used.

See gh-130

spring-graphql-docs/src/docs/asciidoc/boot-starter.adoc

@@ -123,7 +123,7 @@ starter detects such beans adds them to <<index#execution-graphqlsource,GraphQlS
 
 Typically, however, applications will not implement ``DataFetcher`` directly and will
 instead create <<index#controllers,annotated controllers>>. The Boot
-starter declares a `RuntimeWiringConfigurer` called `AnnotatedDataFetcherConfigurer` that
+starter declares a `RuntimeWiringConfigurer` called `AnnotatedControllerConfigurer` that
 detects `@Controller` classes with annotated handler methods and registers those as
 ``DataFetcher``s.
 

spring-graphql-docs/src/docs/asciidoc/index.adoc

@@ -439,10 +439,10 @@ support for detecting `@Controller` and `@Component` classes on the classpath an
 auto-registering bean definitions for them. It also acts as a stereotype for the annotated
 class, indicating its role as a data fetching component in a GraphQL application.
 
-`AnnotatedDataFetcherConfigurer` detects `@Controller` beans and registers their
+`AnnotatedControllerConfigurer` detects `@Controller` beans and registers their
 annotated handler methods as ``DataFetcher``s via `RuntimeWiring.Builder`. It is an
 implementation of `RuntimeWiringConfigurer` which can be added to `GraphQlSource.Builder`.
-The Spring Boot starter automatically declares `AnnotatedDataFetcherConfigurer` as a bean
+The Spring Boot starter automatically declares `AnnotatedControllerConfigurer` as a bean
 and adds all `RuntimeWiringConfigurer` beans to `GraphQlSource.Builder` and that enables
 support for annotated ``DataFetcher``s, see <<boot-graphql-runtimewiring>>.