mix tasks: add legal boilerplate

lib/mix/tasks/pleroma/common.ex

@@ -1,3 +1,7 @@
+# Pleroma: A lightweight social networking server
+# Copyright © 2017-2018 Pleroma Authors <https://pleroma.social/>
+# SPDX-License-Identifier: AGPL-3.0-only
+
 defmodule Mix.Tasks.Pleroma.Common do
   @doc "Common functions to be reused in mix tasks"
   def start_pleroma do

lib/mix/tasks/pleroma/instance.ex

@@ -1,3 +1,7 @@
+# Pleroma: A lightweight social networking server
+# Copyright © 2017-2018 Pleroma Authors <https://pleroma.social/>
+# SPDX-License-Identifier: AGPL-3.0-only
+
 defmodule Mix.Tasks.Pleroma.Instance do
   use Mix.Task
   alias Mix.Tasks.Pleroma.Common

lib/mix/tasks/pleroma/relay.ex

@@ -1,3 +1,7 @@
+# Pleroma: A lightweight social networking server
+# Copyright © 2017-2018 Pleroma Authors <https://pleroma.social/>
+# SPDX-License-Identifier: AGPL-3.0-only
+
 defmodule Mix.Tasks.Pleroma.Relay do
   use Mix.Task
   alias Pleroma.Web.ActivityPub.Relay

lib/mix/tasks/pleroma/uploads.ex

@@ -1,3 +1,7 @@
+# Pleroma: A lightweight social networking server
+# Copyright © 2017-2018 Pleroma Authors <https://pleroma.social/>
+# SPDX-License-Identifier: AGPL-3.0-only
+
 defmodule Mix.Tasks.Pleroma.Uploads do
   use Mix.Task
   alias Pleroma.{Upload, Uploaders.Local}

lib/mix/tasks/pleroma/user.ex

@@ -1,3 +1,7 @@
+# Pleroma: A lightweight social networking server
+# Copyright © 2017-2018 Pleroma Authors <https://pleroma.social/>
+# SPDX-License-Identifier: AGPL-3.0-only
+
 defmodule Mix.Tasks.Pleroma.User do
   use Mix.Task
   import Ecto.Changeset