Acid protection for Biosuits, Ninja, and DeathSquad, and fire protection for DeathSquad

- Biosuits, Ninja armor, and Deathsquad armor are now immune to acid.
- Deathsquad armor is now also fireproof!

Note that acid immunity for your suit and helmet *does not protect your backpack or held items!* Do not get sprayed, or you might just lose that shiny pulse rifle!