Use thiserror for error handling with less boilerplate

src/common/character_set_eci.rs

@@ -245,7 +245,7 @@ impl CharacterSetECI {
             28 => Ok(CharacterSetECI::Big5),
             29 => Ok(CharacterSetECI::GB18030),
             30 => Ok(CharacterSetECI::EUC_KR),
-            _ => Err(Exceptions::notFoundWith("Bad ECI Value")),
+            _ => Err(Exceptions::not_found_with("Bad ECI Value")),
         }
     }