Changes to collision view

[MichaelRelaxen]

This PR adds hero collision support, which is usually used for invisible walls and such throughout the original trilogy.
I learned that chaoticgd had added this to wrench a couple months back, so I figured I would try to add it here as well.

[MichaelRelaxen]

Second commit has some changes to the collision view where it should show more depth. I found that when I was using the program myself that it was difficult to differentiate something far away from something up close. I'd hope that this would help with that, at least I find it useful.

Additionally I made backfaces just a flat gray color instead of the wireframe. I use replanetizer a lot for glitch hunting, and I find it helpful being able to see exactly which walls you can just jump through

Let me know what all makes sense or not and I can probably adjust the PR. I was thinking maybe it'd be good to separate the hero collision from the normal collision with it's own toggle as well.