Switch image version in node

[grossmj]

What about being able to right click a device and reload another device within the same appliance file just a different software version? For example, build a complex topology and find out there is a bug/limitation in a couple of devices or (gasp!) all of your routers. Being able to just change to another version in-situ would be awesome!

Should we reload based on the information found in the template (with versioning) that was used to create the node or the appliance associated with the node (see #1960)?