Christmas Powerups

This update includes the Santa Ball and the Evergreen Sword! These were created as a competition over on my Discord, and they turned out well!

@guigui0246 (on Discord) created the Santa Ball! Go back in time and relive your favorite moments! Use "/trigger Save" when you have 30 or more levels to save your position and time. You can then use the ability to warp back to that exact place and time! (It defaults to the time and place you received the power-up if you haven't set it yourself.)

@sergi0_o (on Discord) created the Evergreen Sword! Need to take down some foes from afar? This sword can help! Right-click to shoot out a projectile that does decent damage. Hold shift while having experience points to charge up for some strength, resistance, and speed! Finally, a good use for the Christmas tree!