patch 7.4.1866

Problem:    Invalid memory access when exiting with EXITFREE defined.
            (Dominique Pelle)
Solution:   Set "really_exiting" and skip error messages.

src/version.c

@@ -753,6 +753,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1866,
 /**/
     1865,
 /**/