Handle "Missing config file" error

[heliomar-pena]

When clone the repository and try to run it at first time, possibly you'll see an error "Cannot find module '../../config'", this could be confuse for the most of users and looks like the app is buggy.

In order to fix this, we should handle the error when importing config file to display a proper error in case the user have not added config file.

So we can guide the user to configurate the project before use it