Added link to novice setup guide and corrected localhost

In this pull request, I have added a link to the newly created Wiki page, [Novice setup guide][novice-setup-guide] and corrected the documentation in the Quick Start to point to [http://localhost:3000/][localhost].

The localhost previously pointed to port `3000` which is contradictory to the [.env][env].

I apologize for combining these two into a single pull request. However, they were so simple I buckled in to the anti-pattern.

[novice-setup-guide]: https://github.com/cantino/huginn/wiki/Novice-setup-guide
[localhost]: http://localhost:3000/
[env]: https://github.com/cantino/huginn/blob/master/.env.example#L6-L8