Extract a common function for builder.createContainer
Extract imageCache for doing cache probes
Removes the cacheBuested field from Builder
Create a new containerManager class which reduces the interface between the
builder and managing containers to 3 functions (from 6)
Signed-off-by: Daniel Nephin <dnephin@docker.com>
Remove runConfig from Builder and dispatchRequest. It is not only on
dispatchState.
Move dispatch state fields from Builder to dispatchState
Move stageName tracking to dispatchRequest.
Signed-off-by: Daniel Nephin <dnephin@docker.com>
