Merge from origin/emacs-26

Merge from origin/emacs-26

24b6e6e (origin/emacs-26) * etc/AUTHORS: Update.
2f22a17 * ; ChangeLog.3 update
0f523de Improve indexing of the user manual
bd5795e Fix url-copy-file arglist
eaa188a ; * admin/notes/bugtracker: Minor additions and updates.
5ed05fb Fix downloading updates for packages with non-ASCII descriptions
e9f2d1f * etc/NEWS: Remove temporary markers.
24fc133 * doc/misc/cc-mode.texi (Config Basics): in @itemize, @asis -...
0f325d1 Don't clobber 'comint-input-autoexpand' in 'read-shell-command'
bc75589 Document restrictions when setting window margins, fringes or...
cc4cebf More improvements for 'read-buffer's doc string
d026d9a * lisp/progmodes/cc-defs.el: Update c-version to 5.33.2 for E...
5dbf08b * src/minibuf.c (Fread_buffer): Minor doc fixes.  (Bug#34749)

# Conflicts:
#	etc/NEWS
#	lisp/url/url-handlers.el