QNX: Add support for lgmon

Added configure test, whether lgmon (liquid graphics performance monitor)
is available. The test is supposed to be positive only for internal
BlackBerry NDKs currently.
Added calls to initialize lgmon and to indicate when an app is ready for
user input.

Change-Id: I5cbc29fb38a86585dcebd14d462436deaa1998aa
Reviewed-by: Wolfgang Bremer <wbremer@blackberry.com>
Reviewed-by: Fabian Bumberger <fbumberger@rim.com>
Reviewed-by: Rafael Roquetto <rafael.roquetto@kdab.com>
Reviewed-by: Kevin Krammer <kevin.krammer@kdab.com>