Points grow exponentially instead of linearly

before:
1s/level – 400 + 500 + 600 + 700 + 800 + 900
3s/level – 133 + 166 + 200 + 233 + 266 + 300

after:
1s/level – 320 + 500 + 720 + 980 + 1280 + 1620
3s/level – 106 + 166 + 240 + 326 + 426 + 540
Merge branch 'master' into gh-pages