NEW FEATURE
.sounds and music are paused when the engine loose focus
.put back the impact particle effect when a bullet dies after its life is complete

BUG FIXES:
.first particle timing fixed
.camera shake could create wrong collisions
.laser and particle impact could create black squares during one frame
.particle locators for enemies were started even if the enemy was inactive
.player homing bullets now don't follow enemies with Collisions with player bullets disabled
.scores animation at the end of a game now takes the same time regardless of the score amount
.removed the default impact sound played when a bullet collided with the player, even with "none" for bullet impact
.Gauge/enemies no shoot also prevented the player to shoot a laser (regression)

NOTE: there is a variable in the .game file to get rid of the bullet end-of-life particle effect: just set PlayerDeadAfterLifeSpwanSfx to "false".