Hotfix 0.25.9

Clearer UI when starting to paint a new gun and a warning if users tries to paint before defining any paint.
M4 small fix in assembly.
Fix for rare problem probably caused by saving a gun in a safe a few versions back.
Small FoV adjustment when holding breath and focusing with iron sights, effect magnitude can be changed in game settings.
Fix for a possibility an attachment from inventory might be lost when gun with the same attachment loaded.