Developer option: extra blob paths (#72)

in-app-manual/configuration.md

@@ -161,6 +161,7 @@ These options are typically not exposed in the UI and must be changed manually i
 |-------|---------|
 | `custom_served_folders` | A map of URLs to file system folders. See below. |
 | `custom_ui_location` | The file system folder where the UI files will be served from, instead of using the embedded UI. Empty to disable. Stash must be restarted to take effect. |
+| `developer_options.extra_blob_paths` | A list of alternative blob paths. These paths will be read for blob files. Blobs will not be written or deleted from these paths. Intended for developer use only. |
 | `max_upload_size` | Maximum file upload size for import files. Defaults to 1GB. |
 | `theme_color` | Sets the `theme-color` property in the UI. |
 | `gallery_cover_regex` | The regex responsible for selecting images as gallery covers |