Arvados

arvados-docker-cleaner does not start on trusty (ubuntu 12.04).

this appears to be because one of its dependencies has a dependency that does not work with python 3.2 (which is the newest version of python3 on trusty).

docker-py seems to require idna, and the version we have is incompatible with the system python and results in a stack trace like this:

 python3 -m arvados_docker.cleaner --quota 250G
Traceback (most recent call last):
  File "/usr/lib/python3.2/runpy.py", line 160, in _run_module_as_main
    "__main__", fname, loader, pkg_name)
  File "/usr/lib/python3.2/runpy.py", line 73, in _run_code
    exec(code, run_globals)
  File "/usr/lib/python3.2/dist-packages/arvados_docker/cleaner.py", line 17, in <module>
    import docker
  File "/usr/lib/python3.2/dist-packages/docker/__init__.py", line 20, in <module>
    from .client import Client, AutoVersionClient # flake8: noqa
  File "/usr/lib/python3.2/dist-packages/docker/client.py", line 19, in <module>
    import requests
  File "/usr/lib/python3.2/dist-packages/requests/__init__.py", line 52, in <module>
    from .packages.urllib3.contrib import pyopenssl
  File "/usr/lib/python3.2/dist-packages/requests/packages/__init__.py", line 39, in <module>
    from . import idna
  File "/usr/lib/python3.2/dist-packages/requests/packages/idna/__init__.py", line 1, in <module>
    from .core import *
  File "/usr/lib/python3.2/dist-packages/requests/packages/idna/core.py", line 10
    _unicode_dots_re = re.compile(u'[\u002e\u3002\uff0e\uff61]')
                                                              ^
SyntaxError: invalid syntax