patch 8.1.0126: various problems with 'vartabstop'

Problem:    Various problems with 'vartabstop'.
Solution:   Fix memory leak.  Fix crash. Add a few more tests. (Christian
            Brabandt, closes #3076)
diff --git a/src/version.c b/src/version.c
index 31db840..4e3770e 100644
--- a/src/version.c
+++ b/src/version.c
@@ -790,6 +790,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    126,
+/**/
     125,
 /**/
     124,