Adding PEP8 only lint rule to tox and Travis.

.travis.yml

@@ -9,4 +9,5 @@ script:
   - tox -e py27
 after_success:
   - tox -e cover
+  - tox -e lint
   - coveralls

gcloud/test_connection.py

@@ -46,6 +46,7 @@ def authorize(self, http):
 
     def test_user_agent_format(self):
         from pkg_resources import get_distribution
-        expected_ua = 'gcloud-python/{0}'.format(get_distribution('gcloud').version)
-        conn = self._makeOne() 
+        expected_ua = 'gcloud-python/{0}'.format(
+            get_distribution('gcloud').version)
+        conn = self._makeOne()
         self.assertEqual(conn.USER_AGENT, expected_ua)

tox.ini

@@ -1,6 +1,6 @@
 [tox]
 envlist =
-    py26,py27,cover,docs
+    py26,py27,cover,docs,lint
 
 [testenv]
 commands =
@@ -28,3 +28,15 @@ commands =
     sphinx-build -b html -d docs/_build/doctrees docs docs/_build/html
 deps =
     Sphinx
+
+[pep8]
+exclude = gcloud/datastore/datastore_v1_pb2.py,docs/conf.py,*.egg/,.*/
+verbose = 1
+
+[testenv:lint]
+basepython =
+    python2.7
+commands =
+    pep8
+deps =
+    pep8