Some messages do not take advantage of "InProcess" nodes.

[tmagrino]

There are a few messages between Workers to Stores that are sent through a socket despite being in the same process. Currently this applies to the messages MakePrincipalMessage and AllocateMessage.

This boils down to an issue of it being easy to forget to add specialized support for messages to InProcess Nodes like InProcessStore and InProcessRemoteWorker.

In the short term, we should check to see if we want to change these messages to also have specialized behavior. In the longer term, it might be worth seeing if there's a way to make it harder to forget to add specialized handling when adding a new message type.