show BoneWall blip on minimap

lost my fade to a friendly bone wall earlier that i didn't know was there, and it frustrated me :P

this is using the sprite for something called "Kill" from minimap_blip.dds. I don't know what it's supposed to be, but I think it's unused. It sorta makes sense as a bone wall, I mostly just didn't want to make a new sprite and override that whole file. i'm not sure what a bone wall blip would look like anyway. 

also i just noticed i used lua-style comments instead of c-style comments. let me know if you want me to fix that. why does UWE do that anyway?