Make Column or MaskedColumn name arg be keyword arg name=None
Add docstring for MaskedColumn
Update table docs to used 'data' and 'name' kwargs in Column/MaskedColumn
Add tests of behavior when column name is not provided
Check Column/MaskedColumn __new__ args for compliance with 0.3 ordering

This is implemented as a decorate on __new__(cls, name=None, data=None, ..)
for Column and MaskedColumn.

The warning is:

In the next major release of astropy (0.3), the order of function
arguments for creating a {class_name} will change.  Currently the order is
{class_name}(name, data, ...), but in 0.3 and later it will be
{class_name}(data, name, ...).  This is consistent with Table and NumPy.

In order to use the same code for Astropy 0.2 and 0.3, column objects
should be created using named keyword arguments for data and name, e.g.:
{class_name}(name='a', data=[1, 2]).
Fix tests so no warnings are generated in Column() calls

This is only complete for table and io.ascii.  All of these tests
run without generating warnings.  This was done to be sure that
all code in astropy.table and astropy.io.ascii is fully compliant
with the new Column args checking, i.e. it will never happen that
a call to astropy.Table can generate a warning to the user.
Pay attention to WARN_COLUMN_ARGS for issuing the args order warning
Merge pull request #731 from taldcroft/table-name-kwarg

Make Column or MaskedColumn name arg be a keyword arg name=None