improved error message

web/src/main/java/lcsb/mapviewer/validator/LoginValidator.java

@@ -30,7 +30,7 @@ public class LoginValidator implements Validator {
 		}
 		if (!LOGIN_PATTERN.matcher((String) value).matches()) {
 			String summary = "Incorrect login.";
-			String detail = "Only alphanumeric characters and \"-_.\" special characters are allowed";
+			String detail = "Only alphanumeric characters and \"-\", \"_\", \".\" special characters are allowed";
 			throw new ValidatorException(new FacesMessage(FacesMessage.SEVERITY_ERROR, summary, detail));
 		}
 	}