Bump levels int to 60
Bump levels int to 60

(Make it possible to access newer levels)

gkathir15/WaniKani-for-Android,dhamofficial/WaniKani-for-Android,Gustorn/WaniKani-for-Android,shekibobo/WaniKani-for-Android,shekibobo/WaniKani-for-Android,diptakobu/WaniKani-for-Android,dhamofficial/WaniKani-for-Android,diptakobu/WaniKani-for-Android,gkathir15/WaniKani-for-Android,Gustorn/WaniKani-for-Android