8 hours, menus and menu hotkeys.
Menu drill down from main menu, added play -> difficulty select (easy, hard, practice). The flyer spawners have health bars. In order to get those health bars working I reorganized some chunks of flyer spawner code. Main menu organization. Pause menu now has buttons to resume, restart and exit to main menu that the player can click, for both easy and hard mode pauses. Prettied up these pause menus. Pausing gives the player access to hotkeys for each of these buttons' functions. Fixed an issue where restarting from the pause menu would lead to pick up highlight resizing issue.