Update pre-commit config to enforace that future imports exist in all files.

Signed-off-by: Daniel Nephin <dnephin@docker.com>

tests/unit/cli/command_test.py

@@ -1,4 +1,5 @@
 from __future__ import absolute_import
+from __future__ import unicode_literals
 
 import pytest
 from requests.exceptions import ConnectionError

tests/unit/cli/main_test.py

@@ -1,4 +1,5 @@
 from __future__ import absolute_import
+from __future__ import unicode_literals
 
 import logging
 

tests/unit/config/config_test.py

@@ -1,5 +1,7 @@
 # encoding: utf-8
+from __future__ import absolute_import
 from __future__ import print_function
+from __future__ import unicode_literals
 
 import os
 import shutil

tests/unit/config/sort_services_test.py

@@ -1,3 +1,6 @@
+from __future__ import absolute_import
+from __future__ import unicode_literals
+
 from compose.config.errors import DependencyError
 from compose.config.sort_services import sort_service_dicts
 from compose.config.types import VolumeFromSpec

tests/unit/container_test.py

@@ -1,3 +1,4 @@
+from __future__ import absolute_import
 from __future__ import unicode_literals
 
 import docker

tests/unit/interpolation_test.py

@@ -1,3 +1,6 @@
+from __future__ import absolute_import
+from __future__ import unicode_literals
+
 import unittest
 
 from compose.config.interpolation import BlankDefaultDict as bddict

tests/unit/multiplexer_test.py

@@ -1,3 +1,6 @@
+from __future__ import absolute_import
+from __future__ import unicode_literals
+
 import unittest
 
 from compose.cli.multiplexer import Multiplexer

tests/unit/project_test.py

@@ -1,3 +1,4 @@
+from __future__ import absolute_import
 from __future__ import unicode_literals
 
 import docker

tests/unit/utils_test.py

@@ -1,4 +1,5 @@
 # encoding: utf-8
+from __future__ import absolute_import
 from __future__ import unicode_literals
 
 from compose import utils