go-rfc1924 RFC1924 base85 encoding It uses charset of following 85 characters: 0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz!#$%&()*+-;<=>?@^_`{|}~ following 9 common characters are left unused: ,.:'"/[]\