function getterSetter(onSet, onGet, value) {
  value = (_.isFunction(value) ? value() : value);

  return function getterSetter(newValue) {
    if(arguments.length) {
      value = (_.isFunction(onSet) ? onSet(newValue, value) : newValue);
    }

    return (_.isFunction(onGet) ? onGet(value) : value);
  };
}
Creates a ready to use GetSet-Function for ngModels with getterSetter option.

@static
@memberOf _
@param {function} [onSet] - The function callback for setting the value.
@param {function} [onGet] - The function callback for getting the value.
@param {*|function} [value] - The default value for this GetSet-Function. Can be the value or a function which returns the value.
@returns {function} The GetSet-Function.