[docs] Patch to enhance literal block language declaration (issue 26462)

[vadmium+py at gmail.com]

http://bugs.python.org/review/26462/diff/16666/Doc/whatsnew/3.2.rst
File Doc/whatsnew/3.2.rst (right):

http://bugs.python.org/review/26462/diff/16666/Doc/whatsnew/3.2.rst#newcode2048
Doc/whatsnew/3.2.rst:2048: .. code-block:: none
On 2016/03/01 23:15:32, Zach Ware wrote:
> This can be 'doscon' instead of 'none'.

FWIW this still produces a warning for me (but maybe it is beneficial if
Sphinx knows about “doscon”):

/media/disk/home/proj/python/cpython/Doc/whatsnew/3.2.rst:2050: WARNING:
Pygments lexer name 'doscon' is not known

http://bugs.python.org/review/26462/