aaactually fix #507: upon channel join, only display last ~d1 of messages in it
aaactually fix #507: upon channel join, only display last ~d1 of messages in it

chc4/urbit,chc4/urbit,urbit/archaeology-factor,rsaarelm/urbit,chc4/urbit,urbit/archaeology-factor,chc4/urbit,chc4/urbit,chc4/urbit,rsaarelm/urbit,chc4/urbit,rsaarelm/urbit,rsaarelm/urbit,chc4/urbit,rsaarelm/urbit,urbit/archaeology-factor,chc4/urbit,urbit/archaeology-factor,urbit/archaeology-factor,urbit/archaeology-factor,rsaarelm/urbit,rsaarelm/urbit,urbit/archaeology-factor,urbit/archaeology-factor,rsaarelm/urbit,chc4/urbit,urbit/archaeology-factor,rsaarelm/urbit,rsaarelm/urbit,urbit/archaeology-factor