change set width to maximum width
Prevent downloading a file twice when identifying and reading it through the registry system.
Stricter simulation of a with statement
address bug 893: nan/inf treatment
added regression test for one case
Add the background graphic for the Windows installer.
Update the documentation to accurately reflect the reality
This is an attempt to fix #507.  It does away with the realloc hack I was using before, and refactors so that when compressing an image, the compression module handles creation of the new Numpy array, and only once CFITSIO is complete and we know how large the compressed data buffer is going to be.  Then compress_hdu() returns the new Numpy array along with the heapsize.  This is a lot less spaghetti-ish than the previous code, and somewhat simpler overall.  Removed the test_insufficient_compression_allocation test since it no longer works correctly with the new code.  But that's okay--the test_lossless_gzip_compression test tests this case for us implicitly, which is why it was failing on Windows in the same way.  This is because the way CFITSIO estimates how much space it will need for the compressed data, it always ends up being less than what's needed for lossless compression.
Merge pull request #893 from keflavich/bug893_convfftnanfix

convolve_fft does not deal with infinity values
Fix Issue #927: VOTables without IDs can not be read by Table.read
Merge pull request #507 from iguananaut/issue-507

astropy.log: The process cannot access the file because it is being used by another process
This should resolve the issue reported in #867 that when running
setup.py install (and in particular when installing Astropy with pip)
the ~/.astropy directory gets generated, when really it shouldn't be.
This commit does a few different things:

 * I've never been too thrilled about having code that can modify the
   system at import time. In the case of generating the default
   astropy.cfg and log I think we have a reasonable excuse, but let's
   try to keep stuff like that in astropy/__init__.py: For that reason I
   moved the logger module initialization code to an `_init_log()`
   function which is called in ``astropy.__init__``.  I also set up a
   default dummy-log so that stuff like ``from astropy import log`` will
   always work even if the real logger hasn't been initialized.

 * For the default config generation I got rid of the environment
   variable hack and just set ``_ASTROPY_SETUP_`` when running the
   subprocess.

   * This requires changing the imports that are only performed when
    ``not _ASTROPY_SETUP_`` to be at least attempted, and only raise an
    exception if we're not in setup mode (this way when the default
    config generator gets to those imports they will still work).

 * Ensured that no attempt is made to create a config file if
   ``_ASTROPY_SETUP_``.
This should fix the problems on Python 3. This forced me to finally go through much of astropy.io.fits and make it at least *importable* under Python 3, since the only places the wcs module was having issues was where it imports from io.fits.
This is necessary for this test to pass on Windows, because otherwise a handle to test.fits is kept open by the mmap.  I suppose this could also use memmap=False.  I thought I had included this commit before I merged the original PR for #507 but apparently I did not.
Merge pull request #930 from iguananaut/issue-507

Followup to #507
Merge pull request #927 from mdboom/vo/table_read_unnamed_tables

Make Table.read find VO tables with no names
Fix #928 -- a votable without a mask can not be created
A few more syntax fixes in io.fits for Python 3. These are easier to make in Astropy than in pyfits, which still supports Python 2.5
Merge pull request #928 from mdboom/vo/writing_table_without_mask

Table.write failing for VO table
As @pllim pointed out, fix documentation about default value of pedantic in astropy.vo