Update requirements; nix test-utils requirement

This updates the versions in the requirements file, removes unneeded
imports in test files and makes a small change so we don't need
test-utils anymore.

requirements.txt

@@ -1,10 +1,10 @@
-# Requirements for building tests
-Django==1.4.1
-mock==1.0b1
-django-nose==1.1
+# Requirements for using tower
+Django==1.4.5
 babel
 jinja2
 translate-toolkit
 -e git://github.com/jbalogh/jingo.git#egg=jingo
--e git://github.com/jbalogh/test-utils.git#egg=test-utils
 
+# Requirements for running the tests
+django-nose==1.1
+mock==1.0.1

tower/tests/test_l10n.py

@@ -1,12 +1,8 @@
-import os
-import base64
-import shutil
 from cStringIO import StringIO
 
 import django
 from django.utils import translation
 
-import jingo
 from jingo.tests.test_helpers import render
 
 from nose import with_setup

tower/tests/test_templates.py

@@ -1,7 +1,5 @@
-import jingo
 from jingo.tests.test_helpers import render
-import jinja2
-from test_utils import eq_
+from nose.tools import eq_
 
 
 def test_safe():