[issue13742] Add a key parameter (like sorted) to heapq.merge

[Raymond Hettinger]

Changes by Raymond Hettinger <raymond.hettinger at gmail.com>:


----------
versions: +Python 3.5 -Python 3.4

_______________________________________
Python tracker <report at bugs.python.org>
<http://bugs.python.org/issue13742>
_______________________________________