devserver: module import cleanup

* Import statements re-grouped: standard lib, third party,
  project-local; separated by a single line, preceded by a single line
  and followed by two lines. Each group is sorted alphabetically.

* Removed unused imports.

BUG=None
TEST=Passes unit tests.

Change-Id: Iee4f78b1256457bd19b2c159a29763ba3404c272
Reviewed-on: https://gerrit.chromium.org/gerrit/33859
Reviewed-by: Chris Sosa <sosa@chromium.org>
Commit-Ready: Gilad Arnold <garnold@chromium.org>
Tested-by: Gilad Arnold <garnold@chromium.org>
diff --git a/gsutil_util.py b/gsutil_util.py
index 4342bf2..bda93c2 100644
--- a/gsutil_util.py
+++ b/gsutil_util.py
@@ -7,6 +7,7 @@
 import subprocess
 import time
 
+
 GSUTIL_ATTEMPTS = 5