ceph-aio: delete mon data if it exists when installing monitor

Signed-off-by: Dunrong Huang <riegamaths@gmail.com>
ceph-aio: output command result

Signed-off-by: Dunrong Huang <riegamaths@gmail.com>
ceph-aio: implement clean command

Signed-off-by: Dunrong Huang <riegamaths@gmail.com>
ceph-aio: refactor command parser

Signed-off-by: Dunrong Huang <riegamaths@gmail.com>