create userland tests

Fix some more tabs.

Parse the "Simulated exit code not 0!" string in gem5 and exit with the proper status

userland/false.c

@@ -0,0 +1,13 @@
+/* Test that emulators forward the exit status properly. */
+
+#include <stdlib.h>
+
+int main(int argc, char **argv) {
+    int ret;
+    if (argc == 1) {
+        ret = 1;
+    } else {
+        ret = strtoull(argv[1], NULL, 0);
+    }
+	return ret;
+}