First "Update"

I just worked on the game a little bit more, and fixed some bugs, while creating some new ones :)
Patch Notes:
- UI is now in the correct positions
- Player isn't instanatly at terminal velocity when walking off platforms
- Added "Next Level" button to level 1, there will be one added to level 2 when, well, a next level exists :)
- Tweaked values a little; jumping and walking around should feel a little nicer

New bugs I already know of:

- The player doesn't spin when walking on a platform

- when hitting a wall, the player stops spinning and moving; this is less of a bug and more of a design choice which will be changed in the next update

that's all :)