Züper Alex now shots ion shots

*New green sprite for ion shots
*Shots now hit trees and explode
Adding spider sprite
Spiders are mortal, spawning and plentyful
Replace tab indenting with 4 space
Merge pull request #1 from alex-ross/asverla-master

Replace tab indenting with 4 space
Merge pull request #5 from asverla/master

Züper Alex now shoots ion shots... there are also spiders...
Fix Tree contructor

Add trees-array
Loop through that array everytime when doing something for all trees
Extract tree position randomizer into Tree#randomizePosition()