rename main to _main to avoid fixing scripts

Signed-off-by: Alfredo Deza <alfredo.deza@inktank.com>
revert scripts/ceph-deploy

Signed-off-by: Alfredo Deza <alfredo.deza@inktank.com>
always raise exit after handling an exception

Signed-off-by: Alfredo Deza <alfredo.deza@inktank.com>
Merge pull request #232 from ceph/wip-scripts

use a cleaner script for `main()` when installing with Python