start module should start server if user does not

[jasonkuhrt]

Currently the presence of an app module causes pumpkins to not scaffold a default one wherein the server is started.

A more gradual approach and module presence for server auto-start would be reflecting on how the API has been used. If server start has been called, then don't. If it has, then do.

Furthermore, it would be nice if this part of the API could literally be hidden from the user under normal circumstances.

[jasonkuhrt]

Added to sprint