Fixed issue when using default parameters value from env.json

[pl3bras]

When using envup with option "--default", it appears that the resulting .env file only contains :

prompt=function prompt(options) {
          return Promise.resolve(options.reduce(function (acc, option) {
            return _extends({}, acc, _defineProperty({}, option.name, option.defaultOption));
          }, {}));
 }

and not the "content" of env.json

[luk707]

Thanks for submitting this, I will have to test this change before I can pull it since a few of my projects depend on it. I will get round to this most likely some point in the week.

[pl3bras]

Hi Luke, Did you already have the time to do some test on this change ?
(BTW, thks for this tool, i really appreciate it)