rpc layer should use a threadpool or some other magic to add concurrency

[Soren Hansen]

If you ask a compute worker to fire up an instance, that could take a while. Some of the operations involved can be quite time consuming, especially if you're not using cow images. All the while, the worker is unable to respond to rpc calls. This means that someone trying to get the console output of a running instance on the same box might have to wait *minutes* for a response. That's not cool.