Update readme.md

change debug mode

add playr/bomb collision animation

fix the leaderboard to appear without any trigger

add leaderboard

update, highscore, send to firebase

in comment code to set up firebase (trying to)

restructure

updated package.json

Merge branch 'changing-game-difficulty'

two lasers if player loses a life, changed bg picture

add player name input field in game-over scene

bullet/bomb collision destroy, sound on bullet/enemy collision

timer that changes bomb max size after time and makes game harder

Merge branch 'master' into bomb-dropping-interval-