patch 8.0.0560: :windo allows for ! but it's not supported

Problem:    :windo allows for ! but it's not supported.
Solution:   Disallow passing !. (Hirohito Higashi)

Author: brammool

src/ex_cmds.h

@@ -1623,7 +1623,7 @@ EX(CMD_wincmd,		"wincmd",	ex_wincmd,
 			NEEDARG|WORD1|RANGE|NOTADR,
 			ADDR_WINDOWS),
 EX(CMD_windo,		"windo",	ex_listdo,
-			BANG|NEEDARG|EXTRA|NOTRLCOM|RANGE|NOTADR|DFLALL,
+			NEEDARG|EXTRA|NOTRLCOM|RANGE|NOTADR|DFLALL,
 			ADDR_WINDOWS),
 EX(CMD_winpos,		"winpos",	ex_winpos,
 			EXTRA|TRLBAR|CMDWIN,

src/version.c

@@ -764,6 +764,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    560,
 /**/
     559,
 /**/