patch 8.1.1514: MS-Windows: wrong shell command with ! in 'guioptions'

Problem:    MS-Windows: wrong shell command with ! in 'guioptions'.
Solution:   Do not check for ! in 'guioptions' when applying 'shellxquote'.
            (Yasuhiro Matsumoto, closes #4519)
diff --git a/src/version.c b/src/version.c
index 76b874e..8420be6 100644
--- a/src/version.c
+++ b/src/version.c
@@ -778,6 +778,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1514,
+/**/
     1513,
 /**/
     1512,