  },
        methods: {
            /**
             * Callback functions
             */
            allCap: function(value) {
                return value.toUpperCase()
            },
            gender: function(value) {
              return value == 'M'
                ? '<span class="label label-info"><i class="glyphicon glyphicon-star"></i> Male</span>'
                : '<span class="label label-success"><i class="glyphicon glyphicon-heart"></i> Female</span>'
            },
            