added metadata support for Module and Theme templates

Oqtane.Client/Services/Interfaces/IModuleDefinitionService.cs

@@ -13,6 +13,6 @@ namespace Oqtane.Services
         Task InstallModuleDefinitionsAsync();
         Task DeleteModuleDefinitionAsync(int moduleDefinitionId, int siteId);
         Task<ModuleDefinition> CreateModuleDefinitionAsync(ModuleDefinition moduleDefinition);
-        Task<List<string>> GetModuleDefinitionTemplatesAsync();
+        Task<List<Template>> GetModuleDefinitionTemplatesAsync();
     }
 }