Add global flag.

URLs, as for importing images.

Walk through /usr/local/etc/dhcpd.conf.template, and try to detect
"fixed-address" and "range" directives.

(By fetching a zone transfer for $OURDOMAIN, and hunting through it
for addresses on the control network.)

image_metadata.php will return an Emulab style image descriptor in XML
format. A remote emulab, given an image URL, will grab this XML
description and use it to create a local descriptor. Inside the
descriptor is an additional URL that is used to download ndz file.

The dumpdescriptor script is now web accessible, and takes a new -e
(export) option that adds the extra URL and other bits that are needed
to import the descriptor and the image.

On the Show Image page, show the metadata URL, which is suitable for
using in an NS file or an rspec (when that code is committed).

Derive type list from underlying image.

Right now, the only addresses it knows are allocated are anything assigned
in the interfaces table with a "ctrl" role, and anything in the dynamic
pool in the virt_node_public_addr table.  (And the reserved network and
broadcast addresses.)

This needs to be extended to anything else we know about!

By default, the output is supposed to be easy to parse and simply
displays the first available address.  More than one available address
can be requested with the "-n" option (e.g. "-n 10" will show the
first ten unallocated addresses).  "-n 0" will show every free
address on the subnet.

The "-a" option (meant more for human consumption) also describes
allocated addresses.  For instance, "ctrladdr -a -n 0" will show
every address on the control net, and what it's used for (if
anything).  "-r" will compress ranges of consecutive free addresses
onto a single line.

To test whether a particular address is in use, invoke it as (e.g.)
"ctrladdr -t 155.98.36.1".  This will give an exit code of 0 if the
address is available, and 1 if used.  Any other options are ignored
if "-t" is specified.

shared nodes (where the user does not have an account and so
must ssh in as root).

fetching images.

Now it only remains in the collective memory of Leigh and I.
That will keep it alive for another 5 minutes or so...

Just use the non-per-experiment entries in switch_stacks rather than looking
for nodes involved in "trunks". The latter doesn't capture our layer1 switch.

an explicit_request attribute in the node_type_attributes table for a
type, and the topology explicitly requests that type, add a desire
to the vtop file call $type-explicit:1.0. An equivalent feature added
by ptopgen will result in those nodes not being allocated unless
explicitly requested.

In the master server, recognize "sharedhost" as a valid proxy node so
that shared vnode host nodes can upload and download images on behalf
of hosted vnodes that are not in the same experiment.

Add "-P <node-i-am-a-proxy-for>" options to frisbee and frisupload clients
allowing them to request images on behalf of other nodes. Previously,
proxying was only really supported in nested instances of the master server.

Make sure that such proxying works when a shared vnode host is serviced by
a subboss; i.e., subboss is proxying for the vnode host which in turn is
proxying for the vnode.

Add metadata_url and imagefile_url.

web interface.

Most of this commit is about making it easier to create the
descriptors (of any kind) The newimageid_ez page now takes an optional
node_id on which to base the new descriptor; most of the fields are
initialized.

You can also provide optional imageid and osinfo arguments, which
allows for slightly less info to be initialized.

Then on the ShowNode page, the link to create an image will take you
to the snapshot image page if the user has write access to the image,
otherwise to the newimageid_iz page to create and snapshot a new
image descriptor.