instead of a string argument.  They perform the send/recv themselves using
a buffer.

This allows taking advantage of non-blocking sockets (in new Synchronet
builds) to be much more responsive.

This should still be compatible with the old socket.send implementation.
The *first* send it does in blocking mode and detects if it's the new or
old socket.send implementation and sets a global variable.  Future sends
know if it's the old or new API and treats them accordingly.

This may make new ircd running on an old build slightly less responsive
when a new user joins or when a new link is established since it blocks
all other ircd activity until the entire send queue has been transmitted (or
the connection is terminated).