change default from np.median to np.ma.median
In ascii.read(), recognize list containing a newline

The `BaseInputter` class tries to detect whether the input is a file
object, filename, or iterable. However it can be fooled into thinking
that the input is a filename if it is a list of strings, one of which is
a newline.
Added new contributors
Added more contributors
Do the Sphinx version check ourselves.

The one built in to Sphinx only handles major.minor.
Merge pull request #2667 from mdboom/doc/sphinx-version-check-ourselves

Do the Sphinx version check ourselves.
Add unit test
Add changelog entry
PR to test Astropy build against what will be tagged astropy-helpers v0.4rc3
Merge pull request #2669 from embray/update-ah

Update astropy-helpers to v0.4rc3
Merge pull request #2648 from lpsinger/read_ascii_list_with_newline

In ascii.read(), recognize list containing a newline
Merge pull request #2562 from astrofrog/update-contributors

Update contributor list
Explicitly use os.linesep in the expected value since that's what's used by the writer code
Just use a common random seed.  Some of these tests (particularly the ones using 0xDEADBEEF as a seed) were being hit by a common bug in some versions of Numpy where Python long objects (which a value like 0xDEADBEEF is converted to on 32-bit systems) are not handled properly by Numpy since it can't guarantee they will fit into a machine integer type
This test wasn't actually making using use of the parametrization; though one of the fitters seems to be failing badly on Win32...
Use a smaller sigma for the random noise in these tests which for now seems to prevent the slsqp fitter from going too far off the reservation (see https://github.com/astropy/astropy/issues/2670)
The float comparison code was excluding the exponent and only comparing the mantissa, which seems odd to me especially in cases that are essentially zero.  This includes the exponent in the values to be compared, for now.
Windows is a lot pickier (at least on Python 2) about unicode values in environment variable dicts passed to subprocess.  Also make sure to use os.pathsep when setting PYTHONPATH
These macros are necessary to build modules that use the WCS API on Windows.  It's unfortunate that this needs to be specified manually, but that does the trick for now
Fix a few more instances of the tests setting unicode environment variables.  It's unclear to me how monkeypatch was causing issues with this, which I fear might be a subtle bug in pytest.  But this gets the job done for now.