introduce disk_info utility
keep box disk type compatibility

- support backword compatibility about box disk format.
 use create_vol_xml_from() to convert disk format automatically
 instead of create_vol_xml() and upload

Signed-off-by: Hiroshi Miura <miurahr@linux.com>
handle storage pool permissions

- add permission block to XML

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

Signed-off-by: Hiroshi Miura <miurahr@linux.com>
import: avoid pool name conflict

Signed-off-by: Hiroshi Miura <miurahr@linux.com>
fix fixnum string convertion

Signed-off-by: Hiroshi Miura <miurahr@linux.com>
Merge pull request #102 from miurahr/support_disk_type_conversion

Support disk type conversion