[view] improvement: displaying a tooltip with the missing dependencies for a supported packaging technology

bauh/api/abstract/download.py

@@ -1,5 +1,5 @@
 from abc import ABC, abstractmethod
-from typing import Iterable, List, Optional
+from typing import Iterable, List, Optional, Tuple
 
 from bauh.api.abstract.handler import ProcessWatcher
 
@@ -41,3 +41,7 @@ class FileDownloader(ABC):
     @abstractmethod
     def list_available_multithreaded_clients(self) -> List[str]:
         pass
+
+    @abstractmethod
+    def get_supported_clients(self) -> tuple:
+        pass