title: Get version defined in mix.exs from a release build
body: <p>Is there any way to get the version number(1.2.3, the following case) in release build? The package is build in distillery.</p>
  
  <pre><code>  def project do
      [app: :sample,
       version: "1.2.3",
       elixir: "~&gt; 1.3",
       elixirc_paths: elixirc_paths(Mix.env),
       compilers: [:phoenix, :gettext] ++ Mix.compilers,
       build_embedded: (Mix.env == :stg) or (Mix.env == :prod),
       start_permanent: (Mix.env == :stg) or (Mix.env == :prod),
       aliases: aliases,
       deps: deps]
    end
  </code></pre>