overriding onBackPressed method

if settings mode is enabled, backpress closes settings window.
otherwise, a confirmation dialog appears to confirm exit.
updated versionCode: 5
updated ide
convertinng osc arguments to int or float if applicable
regain immersive mode after settings panel is closed.

the lower navigation bar seems to stick even after the settings panel is closed
if the settings panel gained input focus earlier. adding an interface method to
notify the parent activity to call regainImmersive method.