Add regression test to check the new user option

Author: Petr Bauch

regression/goto-harness/havoc-global-int-03/main.c

@@ -0,0 +1,10 @@
+int x = 1;
+
+int main()
+{
+  assert(x == 1); //unreachable, hence success
+  assert(x == 2);
+  assert(x == 3);
+
+  return 0;
+}

regression/goto-harness/havoc-global-int-03/test.desc

@@ -0,0 +1,10 @@
+CORE
+main.c
+--harness-type initialise-with-memory-snapshot --memory-snapshot ../load-snapshot-json-snapshots/global-int-x-1-snapshot.json --initial-line 6 --havoc-variables x
+^EXIT=10$
+^SIGNAL=0$
+\[main.assertion.1\] line [0-9]+ assertion x == 1: SUCCESS
+\[main.assertion.2\] line [0-9]+ assertion x == 2: FAILURE
+\[main.assertion.3\] line [0-9]+ assertion x == 3: FAILURE
+--
+^warning: ignoring