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/builder.py b/builder.py
index fdfb50f..53f53a2 100644
--- a/builder.py
+++ b/builder.py
@@ -5,17 +5,19 @@
 # found in the LICENSE file.
 
 """Package builder for the dev server."""
+
 import os
+import subprocess
+import tempfile
+
 from portage import dbapi
 from portage import xpak
 import cherrypy
 import portage
-import subprocess
-import sys
-import tempfile
 
 import log_util
 
+
 # Module-local log function.
 def _Log(message, *args, **kwargs):
   return log_util.LogWithTag('BUILD', message, *args, **kwargs)