Changes to pause screen

- The dpad should work for navigating the menu options
- Pressing the start button should ALWAYS unpause the game, regardless of where the cursor is. In other words, pressing `start` while hovering over `EXIT COURSE` should NOT trigger `EXIT COURSE`. The only way to select an option should be by pressing A.
- The menu should not react to analog input until the stick is centered. In other words, if you pause the game while the stick is ALREADY facing up or down, it should NOT react to that movement. You should be required to center the stick, and THEN it will react to further analog movement.
- When selecting `EXIT COURSE`, there should be a screen asking something like "are you sure?". In this screen, the option that the cursor defaults to should be "no."

If someone triggers an accidental exit course with all of these measures we can just laugh at them tbh

IMO all of this should be mandatory, but if you think it should be optional, then there could be a define called something along the lines of `BETTER_PAUSE_MENU` that enables/disables all of these options in bulk. Except the dpad thingy, there's no reason not to support the dpad.