patch 8.0.0176: cannot use :change inside a function definition

Problem:    Using :change in between :function and :endfunction fails.
Solution:   Recognize :change inside a function. (ichizok, closes #1374)
diff --git a/src/userfunc.c b/src/userfunc.c
index 369d92a..372c9bb 100644
--- a/src/userfunc.c
+++ b/src/userfunc.c
@@ -2085,9 +2085,14 @@
 		}
 	    }
 
-	    /* Check for ":append" or ":insert". */
+	    /* Check for ":append", ":change", ":insert". */
 	    p = skip_range(p, NULL);
 	    if ((p[0] == 'a' && (!ASCII_ISALPHA(p[1]) || p[1] == 'p'))
+		    || (p[0] == 'c'
+			&& (!ASCII_ISALPHA(p[1]) || (p[1] == 'h'
+				&& (!ASCII_ISALPHA(p[2]) || (p[2] == 'a'
+					&& (STRNCMP(&p[3], "nge", 3) != 0
+					    || !ASCII_ISALPHA(p[6])))))))
 		    || (p[0] == 'i'
 			&& (!ASCII_ISALPHA(p[1]) || (p[1] == 'n'
 				&& (!ASCII_ISALPHA(p[2]) || (p[2] == 's'))))))