Strengthen logic/better code in write-cache reporting. Look for new formatting given by newer smartctl

Side-effect of change that added full tmcc build (aka, with SSL) to client.
Even though we currently don't install full tmcc in frisbee MFS (due to
other missing libraries) we at least make sure it builds.

This provides better backward compatibility: it avoids the accidental
dependency on Python 2.7, which is not available under (e.g.) FreeBSD 8.2.

as little of that as possible, so that our images work everywhere.

1. kpartx does not do its own locking, so must protect it from
   concurrent runs during setup.

2. Allow mulitple XEN hosts (up to 4) to set up concurrently via new
   TBScriptLock() shared lock, but revert to exclusive lock if an
   image needs to created or modified.

3. Convert root disk (XEN-STD) to a plain NDZ file from raw LVM bits,
   so that we get some benefit from the buffer cache.

path and since it takes too long, causes the node to get rebooted
when libreboot thinks it has failed.

locks in addition to the default exclusive mode locks, which is
handy for allowing multiple containers to set up in parallel
since in general they won't be changing anything, just reading.

This is essentially a port of tmcc to Python, without any caching (yet)
and an interface tailored to retrieving GENI information.

avoid routing through the control node, but also need to
add this to the SNAT rule for NFS.

"reset" now just unmounts blockstores, it does not destroy them.
Need this so that people can include a SYSVOL blockstore in a custom image
(the only place where "reset" is used). Also, destroying blockstores would
have come as an unpleasant surprise to anyone who created a custom image
and then expected their data to still be around afterward!

Also work around a bizzare bug in BSD sed that happens in the prepare script.
That script does:

     sed -e '/# next line is swap device/,+1d' /etc/fstab

which should remove the matched comment and the line after it (the swapdev
entry). But if there are EXACTLY two additional lines after the matched line,
it would remove both of them (effectively "+2")! So if there was a mount for
a blockstore device after the swap device, prepare would remove that line too.

So in the finest tradition of "if it hurts, don't do it", the blockstore code
makes sure that it adds at least two additional lines.

If number was positive, was converting to "(N)" for some reason.
Parens don't compare well with integers...

Also don't need "bc" just to compute abs(), just use "tr" to remove '-'.

Also adjust the max offset a smidge to 5ms, 1ms is a bit tight.

fumbles around in an infinite loop.

own locking and breaks if two processes call it at the same time. DUMB!

subnet as the control network (as in Utah).

Disabled by default, enabled on Utah Emulab for testing.