edit comps.xml
copy rpms
build comps rpm
copy comps rpm to RedHat/RPMS and RedHat/base/comps.rpm
build centos-yumcache
copy centos-yumcache to RedHat/RPMS
build rpmdb
copy rpmdb to RedHat/RPMS
genhdlist
pkgorder
genhdlist again
buildinstall
mksrpms
splittree
genhdlist on isos