Refactor data handlers + misc fixes

This refactors the data handlers into a more standard/understood model-like architecture, to prepare for a new, more robust config system.

It also fixes a problem with creating new Notes and uploading new Photos via the web interface (related to #58).

Finally, it speeds up docker builds by sending in less files, which aren't necessary or will be built anyway.

This is all in preparation to allow building #13 more robustly.

components/photos/MainPhotos.tsx

@@ -49,6 +49,7 @@ export default function MainPhotos({ initialDirectories, initialFiles, initialPa
 
         const requestBody = new FormData();
         requestBody.set('parent_path', path.value);
+        requestBody.set('path_in_view', path.value);
         requestBody.set('name', chosenFile.name);
         requestBody.set('contents', chosenFile);