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

templates/tools/dockerfile/interoptest/grpc_interop_csharp/Dockerfile.template

@@ -32,6 +32,7 @@
   FROM debian:jessie
   
   <%include file="../../apt_get_basic.include"/>
+  <%include file="../../python_deps.include"/>
   <%include file="../../csharp_deps.include"/>
   <%include file="../../run_tests_addons.include"/>
   # Define the default command.

templates/tools/dockerfile/interoptest/grpc_interop_cxx/Dockerfile.template

@@ -32,6 +32,7 @@
   FROM debian:jessie
   
   <%include file="../../apt_get_basic.include"/>
+  <%include file="../../python_deps.include"/>
   <%include file="../../cxx_deps.include"/>
   <%include file="../../run_tests_addons.include"/>
   # Define the default command.

templates/tools/dockerfile/interoptest/grpc_interop_go/Dockerfile.template

@@ -32,6 +32,7 @@
   FROM golang:1.5
   
   <%include file="../../go_path.include"/>
+  <%include file="../../python_deps.include"/>
   # Define the default command.
   CMD ["bash"]
   

templates/tools/dockerfile/interoptest/grpc_interop_http2/Dockerfile.template

@@ -32,6 +32,7 @@
   FROM golang:1.5
   
   <%include file="../../go_path.include"/>
+  <%include file="../../python_deps.include"/>
   # Define the default command.
   CMD ["bash"]
   

templates/tools/dockerfile/interoptest/grpc_interop_java/Dockerfile.template

@@ -32,7 +32,8 @@
   FROM debian:jessie
   
   <%include file="../../java_deps.include"/>
-  
+  <%include file="../../python_deps.include"/>
+
   # Trigger download of as many Gradle artifacts as possible.
   RUN git clone --recursive --depth 1 https://github.com/grpc/grpc-java.git && ${'\\'}
     cd grpc-java && ${'\\'}

templates/tools/dockerfile/interoptest/grpc_interop_node/Dockerfile.template

@@ -32,6 +32,7 @@
   FROM debian:jessie
   
   <%include file="../../apt_get_basic.include"/>
+  <%include file="../../python_deps.include"/>
   <%include file="../../node_deps.include"/>
   <%include file="../../run_tests_addons.include"/>
   # Define the default command.

templates/tools/dockerfile/interoptest/grpc_interop_php/Dockerfile.template

@@ -32,6 +32,7 @@
   FROM debian:jessie
   
   <%include file="../../apt_get_basic.include"/>
+  <%include file="../../python_deps.include"/>
   <%include file="../../ruby_deps.include"/>
   <%include file="../../php_deps.include"/>
   <%include file="../../run_tests_addons.include"/>

templates/tools/dockerfile/interoptest/grpc_interop_ruby/Dockerfile.template

@@ -32,6 +32,7 @@
   FROM debian:jessie
   
   <%include file="../../apt_get_basic.include"/>
+  <%include file="../../python_deps.include"/>
   <%include file="../../ruby_deps.include"/>
   <%include file="../../run_tests_addons.include"/>
   # Define the default command.

templates/tools/dockerfile/python_deps.include

@@ -11,4 +11,4 @@ RUN apt-get update && apt-get install -y ${'\\'}
 # 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
+RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.0.0a2 six==1.10.0

templates/tools/dockerfile/stress_test/grpc_interop_stress_csharp/Dockerfile.template

@@ -32,6 +32,7 @@
   FROM debian:jessie
   
   <%include file="../../apt_get_basic.include"/>
+  <%include file="../../python_deps.include"/>
   <%include file="../../ccache_setup.include"/>
   <%include file="../../cxx_deps.include"/>
   <%include file="../../gcp_api_libraries.include"/>

templates/tools/dockerfile/stress_test/grpc_interop_stress_cxx/Dockerfile.template

@@ -32,6 +32,7 @@
   FROM debian:jessie
   
   <%include file="../../apt_get_basic.include"/>
+  <%include file="../../python_deps.include"/>
   <%include file="../../ccache_setup.include"/>
   <%include file="../../cxx_deps.include"/>
   <%include file="../../gcp_api_libraries.include"/>

templates/tools/dockerfile/stress_test/grpc_interop_stress_go/Dockerfile.template

@@ -32,6 +32,7 @@
   FROM golang:1.5
   
   <%include file="../../gcp_api_libraries.include"/>
+  <%include file="../../python_deps.include"/>
   <%include file="../../go_path.include"/>
   # Define the default command.
   CMD ["bash"]

templates/tools/dockerfile/stress_test/grpc_interop_stress_java/Dockerfile.template

@@ -32,6 +32,7 @@
   FROM debian:jessie
   
   <%include file="../../apt_get_basic.include"/>
+  <%include file="../../python_deps.include"/>
   <%include file="../../ccache_setup.include"/>
   <%include file="../../cxx_deps.include"/>
   <%include file="../../gcp_api_libraries.include"/>

templates/tools/dockerfile/stress_test/grpc_interop_stress_node/Dockerfile.template

@@ -32,6 +32,7 @@
   FROM debian:jessie
   
   <%include file="../../apt_get_basic.include"/>
+  <%include file="../../python_deps.include"/>
   <%include file="../../node_deps.include"/>
   <%include file="../../gcp_api_libraries.include"/>
   <%include file="../../run_tests_addons.include"/>

templates/tools/dockerfile/stress_test/grpc_interop_stress_php/Dockerfile.template

@@ -32,6 +32,7 @@
   FROM debian:jessie
   
   <%include file="../../apt_get_basic.include"/>
+  <%include file="../../python_deps.include"/>
   <%include file="../../ruby_deps.include"/>
   <%include file="../../gcp_api_libraries.include"/>
   <%include file="../../php_deps.include"/>

templates/tools/dockerfile/stress_test/grpc_interop_stress_ruby/Dockerfile.template

@@ -32,6 +32,7 @@
   FROM debian:jessie
   
   <%include file="../../apt_get_basic.include"/>
+  <%include file="../../python_deps.include"/>
   <%include file="../../ccache_setup.include"/>
   <%include file="../../cxx_deps.include"/>
   <%include file="../../gcp_api_libraries.include"/>

templates/tools/dockerfile/test/csharp_coreclr_x64/Dockerfile.template

@@ -32,6 +32,7 @@
   FROM debian:jessie
   
   <%include file="../../apt_get_basic.include"/>
+  <%include file="../../python_deps.include"/>
   <%include file="../../csharp_deps.include"/>
   
   # Install dotnet SDK based on https://www.microsoft.com/net/core#debian

templates/tools/dockerfile/test/csharp_jessie_x64/Dockerfile.template

@@ -32,6 +32,7 @@
   FROM debian:jessie
   
   <%include file="../../apt_get_basic.include"/>
+  <%include file="../../python_deps.include"/>
   <%include file="../../csharp_deps.include"/>
   <%include file="../../run_tests_addons.include"/>
   # Define the default command.

templates/tools/dockerfile/test/cxx_jessie_x64/Dockerfile.template

@@ -32,6 +32,7 @@
   FROM debian:jessie
   
   <%include file="../../apt_get_basic.include"/>
+  <%include file="../../python_deps.include"/>
   <%include file="../../cxx_deps.include"/>
   <%include file="../../clang_update.include"/>
   <%include file="../../run_tests_addons.include"/>

templates/tools/dockerfile/test/cxx_jessie_x86/Dockerfile.template

@@ -32,8 +32,8 @@
   FROM 32bit/debian:jessie
   
   <%include file="../../apt_get_basic.include"/>
+  <%include file="../../python_deps.include"/>
   <%include file="../../cxx_deps.include"/>
   <%include file="../../run_tests_addons.include"/>
   # Define the default command.
   CMD ["bash"]
-  
\ No newline at end of file