Make channels check for server == nil instead of is_private
Make channels check for server == nil instead of is_private

brpeterman/discordrb,megumisonoda/discordrb,VxJasonxV/discordrb,Roughsketch/discordrb,sarsntony/discordrb,meew0/discordrb,megumisonoda/discordrb,Roughsketch/discordrb,VxJasonxV/discordrb,sarsntony/discordrb,meew0/discordrb,brpeterman/discordrb