Mirror's Story Bugfix 0.21v

Hello! I made a new version of Mirror's Story, where I removed some bugs, and now:
- Hammers can't see killed enemies through the walls.
- You can't explode cans with knife through the walls/standing far away.
- You can't stack killed enemies.
and more. 

Also I added some nice things, such as new sounds (you can switch between jumping sounds, if you don't like old sound), I changed 2nd level doors, and now they aren't annoying.

I hope you will enjoy plaing new version. Bye!