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

Fix for #472.

IMap's containsKey() does not cause the record's last access time to be updated. A record's idle timeout should be reset when it is touched, and according to the documentation "Entry is touched if get, put or containsKey is called." implying this is incorrect behaviour. See #472 for more details.

This pull request contains the fix for this issue and a couple of unit tests to verify that the idle timeout is reset when calling both get() and containsKey().