Got score to transfer between levels and reset

- deleted level.js
- updated score.js < display highscore from local variable> < exit with
‘H’ key
- updated start.js <now creates currentScore local variable and resets
the variable after every game>
- updated hud.js <saves currentScore local variable every time it
changes>
- updated play.js <now loads score from local variable and HUD is now
dynamic>
- updated play2.js <now loads score from local variable and HUD is now
dynamic>