(Most of) the rest of the gated-in-jail changes.
Add a -V option to mkjail.pl telling it to use the virtual control net IP (172.16.0.1) for the default route instead of the real control net IP (18.104.22.168). In this case, it also assigns a virtual control net IP alias (172.17.<pnode>.0) to the physical interface so that the aforementioned routes can actually be installed. Add the same -V option (only valid with -j) in vnodesetup so that we can get it through from bootvnodes. (Also cleaned up the usage message some) The virtual control net address/mask are currently constants in mkjail.pl. At some point they can/should be changed to config time options so that we can easily use this on minibed too. In theory, this (-V) shouldn't be an option and we should just use virtual control net routing all the time. But I want to get some more testing and we have to resolve the minibed conflicts first. So for now, this is an option and it is off by default. Haven't tied this option in with gated yet, so creating a vnode experiment with Session routing still won't work. If you want to do that, create the experiment, watch gated blow up right and left, login to all the physical nodes and change bootvnodes to add -V to the invocation of vnodesetup, and then reboot everything. Now it should be working!