Use Nodemon to auto-restart Rails server

The handy-dandy [Nodemon](https://nodemon.io/) tool is not just for Node.  Today I whipped up an invocation that can restart my Rails server whenever there are changes in the `config` directory tree. Super useful when working heavily with i18n, since changing translation files requires bouncing the server to see changes reflected in the view.

```
$ nodemon --watch config -e rb,yml --exec "rails server"
```

obie-fernandez
January 4, 2017