Update v0.5.5 — Gamma Burst Steam update #345698

Balance changes: -Made enemy level scaling a bit slower overall. -Removed a few Guided Missiles from a few early game enemies (too many Missiles!). -changed Rush Fighter AI to not try ramming the Player, but using a more fighter-like hit and run strategy with a Cannon on the back to shoot at the Player when they chase it. I found the whole ramming and spinning the Player a bit funny at first, but in terms of actual gameplay, this Ship type with rush AI isn't fun to fight against. Bug fixes: -fixed a bug where Enemies would sometimes not properly calculate their rotation to the Player.