Creates an explosion.

start_active: starts with the active pin on.

explosion_type: type of explosion.

explosion_delay: count down timer for explosion in seconds.

damage_amount: amount of damage at explosion center. set to 0 for just a visual effect.

damage_radius: damage amount will be scaled linear from center to radius. 

active pin: when on, the count down timer will count down.

output pin: set to true when the explosion occurs. could be used to chain explosions.
