New enemies and particle effect for shoots!

New enemies have been added on the new version.

The first enemy it's a pentagon. This enemy moves and then shoots a burst of 3 triangles to the player.

The other enemy it's the hexagon. It bounces like a ball and periodically spawns a blast of triangles in various directions.

Particle effect when shoot impacts has been added.

The enemy spawn system has been rebalanced to fit the new enemy types.