* __file__ won't work if we want to invoke modules via -m or if we
figure out how to keep modules from hitting the disk with pipelining.
* module.tmpdir is the new way to place a file where it will be cleaned
automatically.
Change format string to not depend on __file__:
* cloud/amazon/ec2_elb_lb.py
* cloud/amazon/elb_classic_lb.py
Use module.tempdir:
* packaging/os/apt.py
* files/unarchive.py
