Add optional location element too

Author: AdrianCurtin

src/Adapters/Files/FilesAdapter.js

@@ -35,7 +35,7 @@ export class FilesAdapter {
    * - metadata: object containing key value pairs that will be sotred with file (https://docs.aws.amazon.com/AmazonS3/latest/user-guide/add-object-metadata.html)
    * @discussion options are not supported by all file adapters. Check the your adapter's documentation for compatibility
    *
-   * @return {Promise<any>|Promise<{url?: string, name?: string}>} Either a plain promise that should fail if storage didn't succeed, or a promise resolving to an object containing url and/or an updated filename
+   * @return {Promise<any>|Promise<{url?: string, name?: string, location?: string}>} Either a plain promise that should fail if storage didn't succeed, or a promise resolving to an object containing url and/or an updated filename and/or location (if relevant)
    */
   createFile(filename: string, data, contentType: string, options: Object, config: Config): Promise {}