0.2, Added fire and flames!

I decided  that I wanted some more fireworks in my game, so I thought why not add some flammable objects and rockets, and make them interact spectacularly!

Added:

• Planks are now flammable, they can catch on fire using F on them or shooting a rocket in their vicinity
• Other planks in the area have a certain chance to catch fire each frame.
• Rockets, these have a certain explosive power and radius, and a nice little effect.
• Roof model
• Tree model

Modified:

• Larger playing area, and is is also green!
• Lighting

Enjoy!