patch 8.1.1643: sign placement is wrong when 'foldcolumn' is set

Problem:    Sign placement is wrong when 'foldcolumn' is set.
Solution:   Adjust the column computation. (Yee Cheng Chin, closes #4627)
diff --git a/src/gui.c b/src/gui.c
index 634f3fb..7c378c6 100644
--- a/src/gui.c
+++ b/src/gui.c
@@ -2253,7 +2253,7 @@
     int		col = gui.col;
 #ifdef FEAT_SIGN_ICONS
     int		draw_sign = FALSE;
-    int		signcol = 0;
+    int		signcol = col;
     char_u	extra[18];
 # ifdef FEAT_NETBEANS_INTG
     int		multi_sign = FALSE;
@@ -2289,7 +2289,7 @@
 	    --col;
 	len = (int)STRLEN(s);
 	if (len > 2)
-	    signcol = len - 3;	// Right align sign icon in the number column
+	    signcol = col + len - 3;	// Right align sign icon in the number column
 	draw_sign = TRUE;
 	highlight_mask = 0;
     }
diff --git a/src/version.c b/src/version.c
index f71c75c..c7e2a16 100644
--- a/src/version.c
+++ b/src/version.c
@@ -778,6 +778,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1643,
+/**/
     1642,
 /**/
     1641,