Patch by Denver Coneybeare with some test modifications by me.

#17526: fix an IndexError raised while passing code without filename to inspect.findsource().  Initial patch by Tyler Doyle.

#8906: document failureException, longMessage, and maxDiff in the class docstring.  Patch by Boris Feld.

Closes #4159: add LaTeX tabular column specifications to tables that otherwise are cut off or have overlapping text.

  iceweasel, iceape.

correctly check for errors on two CreateFileMapping calls.

from unbuffered (0) to buffering (-1) to match the behavior existing code
expects and match the behavior of the subprocess module in Python 2 to avoid
introducing hard to track down bugs.

from unbuffered (0) to buffering (-1) to match the behavior existing code
expects and match the behavior of the subprocess module in Python 2 to avoid
introducing hard to track down bugs.