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.

handle something as convoluted as

  ftp://joe:secret@insecure.org:8081/hidden/path/to?what=is#this

do it.

to start on a non-page boundary.  Make life safer by rounding out our
edited regions.

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

order so we can just use buffer->fill.

took out the contract to eventually call efree() when it called fetch().

Maintain the most recently loaded image at the start of the list, so that
imgautoselect() will pick it.

after a call to load().

returns the allocated buffer.

"kernel".

refer to them by name from the command line, or build them into a
multiboot module list.

Use setting image->type to disambiguate between "not my image" and "bad
image"; this avoids relying on specific values of the error code.

as allocated by malloc()) versus all other errors, in particular
ENOBUFS (representing a lack of external buffer space, e.g. in a
device's TX queue or a user buffer).

standard and so don't belong in include/elf.h

Add debug autocolourisation to TFTP.

generic ELF loader, to be used by the multiboot code.

and get_memmap() in image/segment.c