patch 7.4.2240

Problem:    Tests using the sleep time can be flaky.
Solution:   Use reltime() if available. (Partly by Shane Harper)

src/version.c

@@ -763,6 +763,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    2240,
 /**/
     2239,
 /**/