refactor to use exception helper factories

src/oned/rss/abstract_rss_reader.rs

@@ -38,7 +38,7 @@ pub trait AbstractRSSReaderTrait: OneDReader {
                 return Ok(value as u32);
             }
         }
-        Err(Exceptions::NotFoundException(None))
+        Err(Exceptions::notFoundEmpty())
     }
 
     /**