Plugin fix: HL2-Box Drops

I have made a fix for the "HL2-Box Drops" plugin installed on alServ2016 & alServ2017.
Now you should get stuff (like defibs, pills, pipes, etc.) when you break boxes also in custom maps.
So look out for boxes and break them when you want more supplies in realism or when you want to defib a fellow team member.
Remember: No respawn in Realism! Dead is dead.

Developer info:

The problem was that custom maps used prop_physics_multiplayer instead of prop_physics.
And therefore the boxes yould not be found when looking for prop_physics with FindEntityByClassname.

I've found the hint for other prop_physics types in the [You must be registered and logged in to see this link.]