SSS Stage1 part5

    Stage1 boss is almost complete, I just need some more polish. Bullets and behaviors are crude.

    Added scores and buffer icons.

    Pause menu, there are two buttons, resume game and quit to title. You can use keyboard/joystick or mouse.

    Enter boss fight, boss hp will pop-up at the bottom of screen.

    Player bullets hit boss.





Changelog:
- Added explore mode background images.
- Added in-game pause menu, resume game or quit to title.
- Added score counter. 
- Added boss HP bar.
- Changed boss 1 behavior.
- Changed formula for scores.
- Fixed player lives counter now it works.
- Fixed boss create.