Time Attack Mode Update

This was a little overdue but the I finally made a big update.

Just added Time Trial mode for each level. To enter this mode you just need to press the R key or X button on the level you want to play. All the level times will be added up to a total world time.

Other than that, I've made a few small updates:

-Survival mode is just gone.
-Cubes are now faster to push
-Bug Fixes

Have fun.