Reverie

I had to rush this release a bit since I'm starting university. I don't know how much time I'll have to work on shaders, so this will probably be the last release for a while.

• Revamped clouds and added a 2nd layer
• Added a settings menu (unfinished)
• End support (unfinished)
• New, more accurate, atmosphere model
• Improved auto-exposure
• Added screenspace distant shadows
• Fixed some bugs
• Some other stuff I forgot about