cli: [fix] clarify import error message (#77)

revizor.py

@@ -6,7 +6,15 @@ Copyright (C) Microsoft Corporation
 SPDX-License-Identifier: MIT
 """
 
-from src.cli import main
+try:
+    from src.cli import main
+except ImportError as orig_import_error:
+    try:
+        from revizor.cli import main
+    except ImportError:
+        print("Unable to import main from src.cli.")
+        print(f"Issue during import of src.cli: `{orig_import_error}`")
+        exit(1)
 
 
 if __name__ == '__main__':