Blue Beam! v0.3.0 gameplay update

updates in version 0.3.0:

• Added new bullet hit sound and particle effects.
• Changed font from outlined to solid color for legibility (it looks even less faithful to the oldies now though).
• All threats now have hitpoints. This is a gamechanger, no more "death blossom" strategies. 
• Slight change to shield spawning interval. Previous code discarded any points earned above the 1000 threshold. 
• Tweaked speeds for almost all entities to balance the game now that they have HP.

Currently working on boring stuff like save data manager and volume slider. Development might come to a pause after these last few UI updates.