doc(readme): correct wrong use of disk.flatList  (#155)
doc(readme): correct wrong use of disk.flatList  (#155)

According to the TS definitions, `disk.flatList` returns `FileListResponse` instead of a `string`. `FileListResponse` is an extension of response and contains `path`, so I believe this update makes the readme match the implementation
Slynova-Org/node-flydrive