[telemetry] Sort imports in Telemetry and its dependents.

tools/telemetry/telemetry/value/histogram_unittest.py

 # Copyright 2013 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 import os
 import unittest
 
 from telemetry import page as page_module
+from telemetry.page import page_set
 from telemetry import value
-from telemetry.page import page_set
 from telemetry.value import histogram as histogram_module
 
 
 class TestBase(unittest.TestCase):
   def setUp(self):
     ps = page_set.PageSet(file_path=os.path.dirname(__file__))
     ps.AddUserStory(page_module.Page("http://www.bar.com/", ps, ps.base_dir))
     ps.AddUserStory(page_module.Page("http://www.baz.com/", ps, ps.base_dir))
     ps.AddUserStory(page_module.Page("http://www.foo.com/", ps, ps.base_dir))
     self.page_set = ps
@@ skipping 53 matching lines @@
       'name': 'x',
       'units': 'counts',
       'buckets': [{'low': 1, 'high': 2, 'count': 1}]
     }
     v = value.Value.FromDict(d, {})
 
     self.assertTrue(isinstance(v, histogram_module.HistogramValue))
     self.assertEquals(
       ['{"buckets": [{"low": 1, "high": 2, "count": 1}]}'],
       v.GetBuildbotValue())