Extend Angular controllers. From http://stackoverflow.com/questions/16539999/angular-extending-controller

angular-controller-extend.js

module.controller('CtrlImplAdvanced', ['$scope', '$controller', function ($scope, $controller) {
    // Initialize the super class and extend it.
    angular.extend(this, $controller('CtrlImpl', {$scope: $scope}));
    // … Additional extensions to create a mixin.
}]);