Order top-level imports, requires, aliases, and uses

[angelikatyborska]

Let's normalize solutions by ordering all of those expressions in this order:

1. All aliases, ordered alphabetically by the module
2. All uses, ordered alphabetically by the module
3. All requiress, ordered alphabetically by the module
4. All importss, ordered alphabetically by the module

All I know is that aliases need to be first because they might affect the other ones (e.g. alias A.B.C; import C won't compile if you swap the order), but the order of the other expressions I chose arbitrarily. Do we have any reasons for any specific order?

Let's not touch any of those expressions that appear after the first function/macro/guard definition. In theory we could also order those expressions when they appear at the top of a function definition, but that's a rare case so maybe there's no point?

Example input:

defmodule Foo do
  import D
  alias X.Y.Z
  alias Banana, as: Ba
  use Z
  import A

  def calc(x), do: x * 2

  import C, only: [bar: 1]
end

Desired output

defmodule Foo do
  alias Banana, as: Ba
  alias X.Y.Z
  use Z
  import A
  import D

  def calc(x), do: x * 2

  import C, only: [bar: 1]
end