Adding Prompt Support

[starburst997]

Allow to add a prompt dialog to enter text (not sure if I broke blackberry).

NativeDialog.onPromptOk = function onPromptOk( str:String )
{
  trace('Prompt: ${str}');
};
NativeDialog.onPromptCancel = onPromptCancel()
{
  trace('Prompt Canceled!');
};

NativeDialog.prompt("Special Code","Enter your code!", "Ok", "Cancel");