Add dockerfile template for python_pyenv_x64 docker image
Generate the dockerfile using generate_projects.sh
Modify run_tests.py to include python3.5 and python3.6
Runs python_jessie_x64 for python versions 2.7 and 3.4, and
python_pyenv_x64 for python versions 3.5 and 3.6
siddharthshukla