crofqueue => renamed set_limit() to set_max_limit()
new class: cauxid, revised API for crofdpt and crofctl
crofdpt_impl, crofctl_impl => revised send methods, throws exceptions for congestion window == 0
added handle_write() method to chain of csocket, crofsock, crofconn, crofchan, crofdpt/crofctl, crofbase
crofctl_impl/crofdpt_impl => removed unnecessary debug output