IMGAPI-478: ignore all ubuntu-certified-* images in mirroring from images.jo to datasets.jo
IMGAPI-478: ignore all ubuntu-certified-* images in mirroring from images.jo to datasets.jo

joyent/sdc-imgapi,numericillustration/sdc-imgapi,numericillustration/sdc-imgapi,joyent/sdc-imgapi,numericillustration/sdc-imgapi,joyent/sdc-imgapi