Shortcut syntax for key/value pair lists and maps used in this tutorial

In most beginner learning resources I have seen, map literals are presented as:
```elixir
animal = %{
:name => "Rex",
:type => "dog",
:legs => 4
}
```

In this repo, we dive straight into using the shortcut for key/value maps (https://github.com/dwyl/learn-elixir#maps).
```elixir
animal = %{
name: "Rex",
type: "dog",
legs: 4
}
```

My understanding is that whilst this is the most common usage, it's also only able to be used if the keys are atoms. Is it worth mentioning that this is a possible syntax so that beginners who see other resources are not confused?