Background grid, v1 !

New grid as a background !

• Explosions and bullet deform it based on the squared distance, clamp to a max deformation.
• Each point will take the latest color, and it's not interpolated between points to get the chunky look
• Light boost is also added and decrease back to 0 

I also want to add particle that move along the grid to light up the points. Probably when an enemy explodes