by tstoeckler: Rename the LibraryType sub-namespace to just Type

libraries.services.yml

src/ExternalLibrary/LibraryManager.php

...ExternalLibrary/Type/LibraryCreationListenerInterface.php

src/ExternalLibrary/Type/LibraryLoadingListenerInterface.php

src/ExternalLibrary/Type/LibraryTypeFactory.php

src/ExternalLibrary/Type/LibraryTypeInterface.php

src/Plugin/libraries/Type/AssetLibraryType.php

src/Plugin/libraries/Type/PhpFileLibraryType.php