This is the interface used to generate file storage orders.
// PlaceStorageOrder place an order for storage file
// - fid: file identification
// - file_name: file name
// - bucket_name: bucket name
// - territory_name: territory name
// - segment: segment info
// - owner: account of the file owner
// - filesize: file size
//
// Return:
// - string: block hash
// - error: error message
func (c *ChainClient) PlaceStorageOrder(fid, file_name, bucket_name, territory_name string, segment []SegmentDataInfo, owner []byte, file_size uint64) (string, error)
