Test for Issue #472 - IMap containsKey() Does Not Reset Idle Timeout

Add a couple of unit tests to new class IMapTest to verify that the idle timeout is reset when calling both get() and containsKey().
Fix for Issue #472 - IMap containsKey() Does Not Reset Idle Timeout

ConcurrentMapManager modified to update the record's last accessed time when containsKey() is called.
Merge pull request #475 from TheDastardlyRaith/472-imap-containskey-idle-timeout

Fix for Issue #472 - IMap containsKey() Does Not Reset Idle Timeout