Add Proguard section to README
Add Proguard section to README

pilgr/Paper,libraua/Paper,libraua/Paper,pjq/Paper,pjq/Paper,shyamkumarm/Paper,bluzwong/Paper,Haegon/Paper,Haegon/Paper,pilgr/Paper,shyamkumarm/Paper,bluzwong/Paper,pilgr/Paper,nguyenhongson03/Paper,nguyenhongson03/Paper