Unexpose subclasses of ResourceFormatLoader and -Saver

ResourceFormatLoader and ResourceFormatSaver are meant to be overridden
to add support for different formats in ResourceLoader and ResourceSaver.
Those should be exposed as they can be overridden in plugins.

On the other hand, all predefined subclasses of those two base classes
are only meant to register support for new file and resource types, but
should not and cannot be used directly from script, so they should not
be exposed.

Also unexposed ResourceImporterOGGVorbis (and thus its base class
ResourceImporter) which are editor-only.

core/io/image_loader.h

@@ -88,7 +88,6 @@ class ImageLoader {
 };
 
 class ResourceFormatLoaderImage : public ResourceFormatLoader {
-	GDCLASS(ResourceFormatLoaderImage, ResourceFormatLoader)
 public:
 	virtual RES load(const String &p_path, const String &p_original_path = "", Error *r_error = NULL);
 	virtual void get_recognized_extensions(List<String> *p_extensions) const;

core/io/resource_format_binary.h

@@ -100,7 +100,6 @@ class ResourceInteractiveLoaderBinary : public ResourceInteractiveLoader {
 };
 
 class ResourceFormatLoaderBinary : public ResourceFormatLoader {
-	GDCLASS(ResourceFormatLoaderBinary, ResourceFormatLoader)
 public:
 	virtual Ref<ResourceInteractiveLoader> load_interactive(const String &p_path, const String &p_original_path = "", Error *r_error = NULL);
 	virtual void get_recognized_extensions_for_type(const String &p_type, List<String> *p_extensions) const;
@@ -162,7 +161,6 @@ class ResourceFormatSaverBinaryInstance {
 };
 
 class ResourceFormatSaverBinary : public ResourceFormatSaver {
-	GDCLASS(ResourceFormatSaverBinary, ResourceFormatSaver)
 public:
 	static ResourceFormatSaverBinary *singleton;
 	virtual Error save(const String &p_path, const RES &p_resource, uint32_t p_flags = 0);

core/io/resource_importer.h

@@ -37,8 +37,6 @@ class ResourceImporter;
 
 class ResourceFormatImporter : public ResourceFormatLoader {
 
-	GDCLASS(ResourceFormatImporter, ResourceFormatLoader)
-
 	struct PathAndType {
 		String path;
 		String type;

core/io/translation_loader_po.h

@@ -36,7 +36,6 @@
 #include "core/translation.h"
 
 class TranslationLoaderPO : public ResourceFormatLoader {
-	GDCLASS(TranslationLoaderPO, ResourceFormatLoader)
 public:
 	static RES load_translation(FileAccess *f, Error *r_error, const String &p_path = String());
 	virtual RES load(const String &p_path, const String &p_original_path = "", Error *r_error = NULL);