Merge changes made in Gnus master

Merge changes made in Gnus master

2013-08-01  Lars Magne Ingebrigtsen  <larsi@gnus.org>
* gnus.texi (Basic Usage): Mention that warp means jump here.
  (The notmuch Engine): Mention notmuch.

2013-08-01 Lars Magne Ingebrigtsen <larsi@gnus.org>
* message.el (message-ignored-news-headers): Delete X-Gnus-Delayed
  before sending.
* dgnushack.el (dgnushack-compile): Add a temporary check for
  gnus-icalendar.
* mm-decode.el (mm-command-output): New face.
  (mm-display-external): Use it.

2013-08-01 Kan-Ru Chen (陳侃如) <kanru@kanru.info> (tiny change)
* nnmbox.el (nnmbox-request-article): Don't change point.

2013-08-01 Lars Magne Ingebrigtsen <larsi@gnus.org>
* gnus-icalendar.el (gnus-icalendar-event:inline-reply-buttons):
  Include `handle' parameter.

2013-08-01 Jan Tatarik <jan.tatarik@gmail.com>
* gnus-icalendar.el: New file.

2013-08-01 Lars Magne Ingebrigtsen <larsi@gnus.org>
* gnus-int.el (gnus-warp-to-article): Mention that warp means jump.
* gnus-uu.el (gnus-uu-mark-thread, gnus-uu-unmark-thread): Work with
  dummy roots, too.

2013-08-01 David Edmondson <dme@dme.org>
* mml2015.el (mml2015-epg-key-image-to-string): Protect against bugging
  out on ttys.

2013-08-01 Lars Magne Ingebrigtsen <larsi@gnus.org>
* gnus-start.el (gnus-dribble-save): Only save the dribble file if it's
  not empty.