Support keyboard input and display of U+1E9E

* lisp/international/latin1-disp.el (latin1-display):
* lisp/international/iso-transl.el (iso-transl-char-map)
(iso-transl-language-alist): Add U+1E9E capital sharp S.

lisp/international/iso-transl.el

@@ -76,6 +76,7 @@
     ("\"E"  . [?Ë])
     ("\"I"  . [?Ï])
     ("\"O"  . [?Ö])
+    ("\"S"  . [?ẞ])
     ("\"U"  . [?Ü])
     ("\"a"  . [?ä])
     ("\"e"  . [?ë])
@@ -324,6 +325,7 @@ sequence VECTOR.  (VECTOR is normally one character long.)")
     ("German"
      ("A"  . [?Ä])
      ("O"  . [?Ö])
+     ("S"  . [?ẞ])
      ("U"  . [?Ü])
      ("a"  . [?ä])
      ("o"  . [?ö])

lisp/international/latin1-disp.el

@@ -124,6 +124,7 @@ display for all of `latin1-display-sets'.  See also
 	     (?\™ "TM")	;; TRADE MARK SIGN
 	     (?\› ">") ;; SINGLE RIGHT-POINTING ANGLE QUOTATION MARK
 	     (?•  "·")
+             (?ẞ "SS") ;; LATIN CAPITAL LETTER SHARP S
 	     )))
 	  (setq latin1-display t))
     (mapc #'latin1-display-reset latin1-display-sets)