Make testing toolchain python 3.x compliant

six is necessary for making these scripts cross compatible
between python 2.x and 3.x

Changes:
Add six to python_deps.include
Include python_deps.include to all Dockerfile templates in test directory
Include python_deps.include to all Dockerfile templates in stress_test directory
Include python_deps.include to all Dockerfile templates in interop_test directory
Replace print statements with print function calls (from futute..)
Replace .iteritems() with .items() wherever necessary
use six.moves to import BaseHTTPServer
Generate new dockerfiles using generate_projects.sh
diff --git a/tools/run_tests/report_utils.py b/tools/run_tests/report_utils.py
index 35dcaca..5648a69 100644
--- a/tools/run_tests/report_utils.py
+++ b/tools/run_tests/report_utils.py
@@ -29,6 +29,8 @@
 
 """Generate XML and HTML test reports."""
 
+from __future__ import print_function
+
 try:
   from mako.runtime import Context
   from mako.template import Template
@@ -60,7 +62,7 @@
   root = ET.Element('testsuites')
   testsuite = ET.SubElement(root, 'testsuite', id='1', package='grpc', 
                             name='tests')
-  for shortname, results in resultset.iteritems(): 
+  for shortname, results in resultset.items():
     for result in results:
       xml_test = ET.SubElement(testsuite, 'testcase', name=shortname) 
       if result.elapsed_time:
@@ -83,10 +85,10 @@
   try:
     mytemplate = Template(filename=template_file, format_exceptions=True)
   except NameError:
-    print 'Mako template is not installed. Skipping HTML report generation.'
+    print('Mako template is not installed. Skipping HTML report generation.')
     return
   except IOError as e:
-    print 'Failed to find the template %s: %s' % (template_file, e)
+    print('Failed to find the template %s: %s' % (template_file, e))
     return
 
   sorted_test_cases = sorted(test_cases)