iSCSI hack.

reflect the fact that they allocate and deallocate user memory (i.e.
things reached through a userptr_t).

will enable us to cascade async operations, which is necessary in order to
properly support DNS.  (For example, an HTTP request may have to redirect
to a new location and will have to perform a new DNS lookup, so we can't
just rely on doing the name lookup at the time of parsing the initial
URL).

Anything other than HTTP is probably broken right now; I'll fix the others
up asap.

that switches from line-oriented to byte-oriented partway through, such as
HTTP.

Add debug autocolourisation to TFTP.

copy_{to,from}_phys.

can't modify it).

routing table entry just to fool ipv4.c any more.

TargetAddress from the login response, because we still need the old
address while we close the connection!

"Permission denied" as an error text to strerror().

abstraction.

determine iSCSI boot parameters.

Remove the now-totally-obsolete sockaddr_in field from tcp.h.

information in NVS.

Added CHAP authentication