Added modules that would lead to setuptools being imported to the unsafe import list in configuration file generation, since if setuptools is not installed, it is *not* downloaded automatically at runtime (and this causes issues if importing astropy for the first time and generating the configuration file).
Fixed setup_helper -> setup_helpers and version_helper -> version_helpers
Merge pull request #651 from astrofrog/config/fix-no-setuptools

setup.py build fails without setuptools installed?
updated ConfigurationItem option usage to accept all non-string iterables
Updated configuration documentation to better explain types
Ensure all file objects are closed when reading/writing HDF5, and in HDF5 tests.
Merge pull request #677 from astrofrog/io/fix-hdf5-open-fileobj

Ensure all file objects are closed when reading/writing HDF5
Merge pull request #665 from eteq/issue-665

Document list and tuple behavior in ConfigurationItem's defaultvalue
Add "unclosed file detection" to the testing framework.

Fix unclosed file bug in logger.py
Fix unclosed file bug in wcs.
Fix unclosed file bug in io.ascii.
Add open_file_detection_test
Update to alternate implementation that uses lsof
Check that we can successfully run lsof
Python 3 fixes
Fix for Python 3.x (to do bungled rebase)