Fix Gnus-related issues reported by David Kastrup <dak@gnu.org> in
<http://lists.gnu.org/archive/html/emacs-devel/2014-07/msg00370.html>.
* atimer.c (timerfd_callback): Always read expiration data.
Add comment.
(turn_on_atimers) [HAVE_TIMERFD]: Disarm timerfd timer.
* process.c (add_timer_wait_descriptor): Add timer descriptor
to input_wait_mask and non_process_wait_mask as well.
Fix some issues with setting the frame height.

* frame.c (x_set_frame_parameters): Revert part of 2014-07-24
change that added the top margin height to the requested height
and revert (undocumented) part of 2014-07-28 change that changed
the logic of whether a size change occurred.
* net/tramp-sh.el (tramp-get-remote-python): Also search for
executables named "python2" or "python3".
(tramp-get-remote-uid-with-python): Use parentheses around
arguments to `print' to make it compatible with Python 3.
(tramp-get-remote-gid-with-python): Ditto.
Fix Changelog typo, introduced by last commit.
* lisp/progmodes/python.el (inferior-python-mode): Make input prompts
read-only.