Support VTS nodes within Jacks

[MarshallBrinn]

We would like to try to integrate VTS nodes into Jacks. There are a number of challenges:

• VTS manifests and requests are very different from the ones Jacks understands
• VTS nodes need to be allocated before regular compute nodes, so that the name of the shared-vlans can be put in the compute node requests (not unlike stitcher)

There are many ways to go about this, all of them tricky and potentially ugly.

• Make a separate AM that represents a co-located VTS/IG site and does the delegating/joining
• Make a plugin to omni or stitcher to handle calls to VTS sites and their corresponding compute nodes
• Push this into Jacks (make it understand VTS rspecs and extensions)
• Push this into VTS (make calls to VTS do the corresponding calls to the associated IG AM)

Per Sarah, it is best to treat VTS AM and a co-located IG AM as a single site within Jacks and handle the splitting/joining of operations to separate AM's behind the scenes. That certainly would be more convenient for the user (though harder to implement).

Not sure how to proceed. This is certainly in the nice-to-have realm, but it would be a very good way to make VTS more readily accessible and integrated for ordinary GENI users.