Mark crashing tests as failed

If a test generates a core dump, it is marked as a failure.

maxscale-system-test/copy_logs.sh

@@ -51,3 +51,7 @@ else
 	rsync -a --no-o --no-g LOGS $logs_publish_dir
 fi
 
+for i in `find $logs_dir -name 'core*'`
+do
+    test -e $i && echo "Test failed: core files generated" && exit 1
+done

maxscale-system-test/testconnections.cpp

@@ -827,17 +827,16 @@ int TestConnections::copy_all_logs()
 
     sprintf(str, "%s/copy_logs.sh %s", test_dir, test_name);
     tprintf("Executing %s\n", str);
+
     if (system(str) != 0)
     {
         tprintf("copy_logs.sh executing FAILED!\n");
-        return 1;
+        exit(1);
     }
-    else
-    {
+
     tprintf("copy_logs.sh OK!\n");
     return 0;
 }
-}
 
 int TestConnections::copy_all_logs_periodic()
 {