Squashed commit of the following:
apps/graphics/twm4nx: The calibration seems to be functional. Needs more testing.
apps/graphics/twm4nx: Extend event handling to support receiving raw, uncalibaated touchscreen inputs. This is needed for touchscreen calibration.
apps/graphics/twm4nx: Extend event handling to support shutting down of externally controlled windows. This is need to end the calibration sequence.
apps/graphics/twm4nx: CCalibration now compiles okay, but is missing event handling logic for touchscreen input and for window termination.
apps/graphics/twm4nx: Move application-related files into different directories to separate them from the core Twm4Nx files.
apps/graphics/twm4nx: A little more progress on calibration display.
app/graphics/twm4ndx: Add files that will support a calibration display. This initial commit is simply the calibration display from NxWM and is not hooked into the configuration or build systems.
apps/graphics/twm4ndx: Compile out cursor support if we are using a mouse
apps/graphics/twm4nx: Replace most usage of NUL-terminated C strings with NXWidgets::CNxString.
apps/graphics/twm4nx: Add initial support for the main menu. The main menu will come up when a left click is performed on the background. The main menu is used for starting applications. The adds the CMainMenu class that implements the main menu and an IApplication interface class the provides th template for how any external C++ application can add itself to the Main Menu.
Still missing is the logic that responds to the meny item selection and sends the event to the Main Menu as well as the logic in the Main Menu that handles the event and either brings up a sub-menu or starts and application.
Things are still basically functional after these changes, but my gut feeling is these changes added some instabilities that will need to be smoothed out.
