Improve Terms of Service

Signed-off-by: Thomas Citharel <tcit@tcit.fr>

lib/service/git_status.ex

@@ -0,0 +1,21 @@
+defmodule Mobilizon.Service.GitStatus do
+  @moduledoc """
+  See https://github.com/CrowdHailer/git_status/
+  """
+  require Logger
+
+  @commit (case System.cmd("git", ["describe", "--tags", "--dirty"]) do
+             {hash, 0} ->
+               String.trim(hash)
+
+             _ ->
+               Logger.warn("Could not read git commit hash")
+               "UNKNOWN"
+           end)
+
+  @doc """
+  The git commit hash read at compile time, if present
+  """
+  @spec commit :: String.t()
+  def commit, do: @commit
+end