A minor release with a lot of feature polish.

Player-visible changes

1. Powerup spawn logic was overhauled so that the player will see fewer powerups which they can't immediately use.
2. Added the PowerShot powerup. This will give your shots additional momentum, which will allow you to push back some of those tougher enemies more easily.
3. Reduced the damage multipliers per skill level.
4. Enemy sounds are more clearly doppler-shifted, so if you listen carefully you can tell whether they are moving toward you or away from you.
5. Side-swipe collisions will now be less damaging to the player.
6. Picking up a cow gives the player a $1000 bonus.
7. Overhauled the asteroid allocation logic to stretch the late game.
8. Reduced the multipliers for the thrust augmenter and the fast reaction wheel.
9. Added Recovered Resources View on the main screen.
10. Added currency symbol selection to the Options screen.
11. Improved visibility of diamond asteroids.
12. Fix some meter display bugs.
13. Animate the HUD display of shield strength.