Ubdate 3

Update 3: 

• -Slight value changes to some upgrades 
• -High cannon damage now creates more bullets after a couple upgrades 
• -Dead tanks now cant be destroyed, will despawn after a while (so you cant just sit in one spot as easily) 
• -Added "Agility" upgrade 
• -Healthbar now gets longer the more hp you have 
• -An average of 1 extra tank will spawn per round
• -Little dude cant walk through the rocks anymore