do manual repo files when specifying --dev (centos)

Signed-off-by: Alfredo Deza <alfredo.deza@inktank.com>
do manual repo files when specifying --dev (fedora)

Signed-off-by: Alfredo Deza <alfredo.deza@inktank.com>
Merge pull request #226 from alfredodeza/8893

make `--dev` flags not install the `ceph-release` package