Merge from origin/emacs-26

Merge from origin/emacs-26

56e3e4f Improve indexing in the ELisp manual
7a4992a More Symbola-related extensions for default fontset
4ae0a75 Better support for display of U+1F900..U+1F9FF block
8f0c788 Improve documentation of 'edit-abbrevs-mode'
3c643e7 ; NEWS tweak
477414a Improve documentation of 'dired-do-compress'
9c09b1d ; * etc/NES: Minor change in the description of Dired's 'Z'.
52715e3 Improve doc string and display of 'describe-character'
93242b1 * etc/NEWS: Clarify what 'Z' does in Dired.  (Bug#33450)
0d59ae3 Update the docs of object internals

Conflicts:
	etc/NEWS