patch 7.4.1515
Problem:    Channel test is a bit flaky.
Solution:   Instead of a fixed sleep time wait until an expression evaluates
            to true.
diff --git a/src/version.c b/src/version.c
index b98ff53..8b5385e 100644
--- a/src/version.c
+++ b/src/version.c
@@ -744,6 +744,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1515,
+/**/
     1514,
 /**/
     1513,