LPS-44428 Adding a new constant for vocabulary Id in Field
LPS-44428 Copy from DLFolderIndexer, no logic changes
LPS-44428 Adding AssetCategoryIndexer
LPS-44428 Copy from DLFolderIndexer, no logic changes
LPS-44428 Adding AssetVocabularyIndexer
LPS-44428 Registering AssetCategoryIndexer and AssetVocabularyIndexer to Asset Category Admin Portlet