Dawnsbury Days 2.53 [firearms mod support]

This minor patch adds capability to support the Double Barrel trait of an upcoming mod by SudoTrainer.

• Modding: Added StrikeModifiers.IncreaseWeaponDieByOneStep.
  
• Modding: Adding Traits.Remove.
  
• Modding (example mods): Fixed that the Kobold example mod crashed on startup.