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/dockerfile/test/cxx_jessie_x86/Dockerfile b/tools/dockerfile/test/cxx_jessie_x86/Dockerfile
index abd3e42..bee0849 100644
--- a/tools/dockerfile/test/cxx_jessie_x86/Dockerfile
+++ b/tools/dockerfile/test/cxx_jessie_x86/Dockerfile
@@ -63,6 +63,21 @@
 # Build profiling
 RUN apt-get update && apt-get install -y time && apt-get clean
 
+#====================
+# Python dependencies
+
+# Install dependencies
+
+RUN apt-get update && apt-get install -y \
+    python-all-dev \
+    python3-all-dev \
+    python-pip
+
+# Install Python packages from PyPI
+RUN pip install pip --upgrade
+RUN pip install virtualenv
+RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.0.0a2 six==1.10.0
+
 #=================
 # C++ dependencies
 RUN apt-get update && apt-get -y install libgflags-dev libgtest-dev libc++-dev clang && apt-get clean