Add debug feedback on module exceptions

src/delarte/__main__.py

@@ -139,7 +139,6 @@ def main():
     http_session = requests.sessions.Session()
 
     try:
-
         program_sources = fetch_program_sources(args["URL"], http_session)
 
         rendition_sources = _select_rendition_sources(
@@ -165,6 +164,8 @@ def main():
         download_targets(targets, http_session, _create_progress())
 
     except UnexpectedError as e:
+        if args["--debug"]:
+            raise e
         print(str(e))
         print()
         print(
@@ -182,15 +183,15 @@ def main():
         return 1
 
     except ModuleError as e:
-        print(str(e))
         if args["--debug"]:
-            print(repr(e))
+            raise e
+        print(str(e))
         return 1
 
     except requests.HTTPError as e:
-        print("Network error.")
         if args["--debug"]:
-            print(str(e))
+            raise e
+        print("Network error.")
         return 1