code: function (property, messager) {
  			this.base('initialize')([property], function (value) {
  				return value != null;
  			}, messager || function () {
  				return i18n['ch/maenulabs/validation/ExistenceCheck'].message();
  			});
  		}
docs: Creates an ExistenceCheck.
  
  @constructor
  
  @param String property The property name
  @param Function [messager] The messager