Changes to "panic" mode.
* Any experiment can now be paniced; formerlly, only firewalled experiments could be paniced. There are new options in the admin menu section of the Show Experiment page. ProtoGeni experiments can also be paniced. At the moment, this is an admin-only option. Should it be? * There are now two levels of panic. The first level (and the default) is to throw all the machines into the Admin MFS and reboot them. Level 2 (OH NO!) disables the control network. Not sure we need two levels, but hey, it was easy. * Admins can swapout a paniced experiment. There is new code in tbswap to watch for a paniced experiment, and zaps the disks. * Add menu option to clear the panic. Also admin-only. * Minor tweaks to Show Experiment when experiment is paniced.