(mostly nonfunctional) GUI changes

it's really not much:
-changed show() in Display to setVisible(boolean), so that no deprecated code is used
-changed the sizing code in the GuiDisplays to use the full screen (setExtendedState)
-reworked the downloading GUI. It now uses a progress bar, and is a little shorter
-changed show() in Display to setVisible(boolean), so that no deprecated code is used
-changed the sizing code in the GuiDisplays to use the full screen (setExtendedState)
-reworked the downloading GUI. It now uses a progress bar, and is a little shorter