RatAttack: added new VA Event ((RatAttack.invalidRatsignal))

Fires when a signal doesn’t match the current RegEx. By default warns with TTS and writes the signal to `%appdata%\RatAttack\ratsignal.error.log`.

plugins/RatAttack/RatAttack.cs

@@ -111,6 +111,7 @@ namespace RatAttack
             catch (ArgumentException e)
             {
                 Log.Error(e.Message);
+                Commands.TriggerEvent("RatAttack.invalidRatsignal", parameters: new dynamic[] { new string[] { ratsignal.Signal } });
             }
             catch (Exception e)
             {