Reorganize fetching configmap and add more comments
Reorganize fetching configmap and add more comments

kubernetes-incubator/external-storage,dhirajh/external-storage,dhirajh/external-storage,childsb/external-storage,childsb/external-storage,humblec/external-storage,dhirajh/external-storage,childsb/external-storage,humblec/external-storage,kubernetes-incubator/external-storage,humblec/external-storage,dhirajh/external-storage,kubernetes-incubator/external-storage