Add example output to multi_alarm_simple_overflow README

examples/tests/multi_alarm_simple_overflow_test/README.md

@@ -11,3 +11,21 @@ is at 32kHz).
 If the virtual alarm library is buggy, this test might fail by
 scheduling the 1 second alarm _after_ the longer wrapping alarm, and
 it won't fire immediately.
+
+# Example Output
+
+Correct:
+
+```
+2 10512380 10511329
+1 3 1
+```
+
+Incorrect:
+
+(after no output for an entire clock overflow, e.g. ~7 minutes)
+
+```
+1 3 1
+2 10512341 10511329
+```