Added a FAQ item that presents code for a StopWatch variant that does not use state-local storage and explains the drawbacks of that approach

[SVN r30258]

libs/statechart

@@ -1 +1 @@
-Subproject commit 11c9dc5b3216c8f687a1b8c034d34722476b0c0d
+Subproject commit a1c3c1771fef350433ead41c7806e14635e9398e