Revert "Wrap FedmsgConnection#send and FedmsgConnection#connect in an (impure) IO monad, because it is still useful"

This causes some weirdness. :(

This reverts commit 9361766b03a8f0948e40600cfbda4db1eef0d29a.
unfinalize these so the constructor can set them

Signed-off-by: Ricky Elrod <ricky@elrod.me>