RC5 release, for Chaos Engine

- Fixed fading textures to have full mipmap chain (no longer loads garbage on chaos or with -forceallmips)
- Added nogrenade on 2nd jump
- Adjust fadein length of fading textures on vert so players can see where to go quicker
- Fixed some textures on pillars on vert
- Added portals on last, instead of landmark teleport stuff
- Fixed catapults not working
- Moved fall sound trigger to use a filter_velocity instead of enabling/disabling