Added link to post mortem article in readme

updated README

[fix] prevent flying off level in level 9

[perf] optimized bundle size (0 bytes left)

[fix] fixed silenced sound when sliding on slopes

[fix] removed unsafe savepoint in level 3

updated README.md

updated README.md

[impr] level tweaks

[feat] implemented time counter

[impr] level tweaks

[perf] small bundle size improvements

[perf] more aggresive svg bundling (lower float precision for paths)

[ref] removed sounds as asset, using zzfx directly

[fix] returned missing level