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/artifact_targets.py b/tools/run_tests/artifact_targets.py
index bd1269c..e9267be 100644
--- a/tools/run_tests/artifact_targets.py
+++ b/tools/run_tests/artifact_targets.py
@@ -40,7 +40,7 @@
   environ['RUN_COMMAND'] = shell_command
 
   docker_args=[]
-  for k,v in environ.iteritems():
+  for k,v in environ.items():
     docker_args += ['-e', '%s=%s' % (k, v)]
   docker_env = {'DOCKERFILE_DIR': dockerfile_dir,
                 'DOCKER_RUN_SCRIPT': 'tools/run_tests/dockerize/docker_run.sh',