Update 1.51b: Improvements and hotfix

- Addition: Floor display in "Battle Plan" mode remains in memory for the next use - Addition: Invisible walls around the aircraft carrier to prevent accidental falls - Improvement: Global lighting rendering on the training map - Improvement: The elevator controls on the aircraft carrier now blink to make them easier to locate - Improvement: Objectives are less likely to be located in a dynamic campaign based on the campaign's progression - Improvement: Stats for the "Old School" stock for the "V4 Classic" assault rifle - Fix: Equipment display error when the player pressed the interaction key too quickly after eliminating an enemy in melee combat - Fix: Decals on the aircraft carrier may not have displayed correctly - Fix: Interior of the aircraft carrier was affected by weather conditions - Fix: Lights inside the aircraft carrier could sometimes display the wrong texture - Fix: Knives and radios were not accounted for in the inventory weight - Fix: Enemy corpses could disappear while in the player's line of sight