add scp method

Signed-off-by: Hiroshi Miura <miurahr@linux.com>
use subprocess to call rsync/scp

Signed-off-by: Hiroshi Miura <miurahr@linux.com>
fix error messages

Signed-off-by: Hiroshi Miura <miurahr@linux.com>
expand path and files

Signed-off-by: Hiroshi Miura <miurahr@linux.com>