How would I go about disabling the attempts by bitake to get files from the
available PREMIRRORS and MIRRORS? I have a recipe which I am developing
locally, and as part of the build process it fetches files from a Subversion
repository on my local network; however it keeps trying to download them
from the PREMIRRORS and (if my repository is inaccessible) the MIRRORS
locations. How can I force it to use only the source I provide (preferably
only for this recipe)?