Django-file-form

- Issue 315: file is not removed after form error
- Issue 313: allow using custom storage and custom cache (thanks to Balazs Endresz)

- Issue 304: rewrite frontend in typescript
- Issue 305: don't change migration when setting changes (thanks to Lionqueen94)
- Issue 307: add French translations; also make translations discoverable by makemessages (thanks to Simon Maillard)

- Issue 298: directory support for drop area
- Issue 300: add migration so makemigrations will not create one (thanks to Lionqueen94)

- Issue 290: add javascript callbacks (thanks to Peter Dekkers)
- Issue 296: fix progress bar
- Issue 297: add retry delays

- Issue 266: allow relative `FILE_FORM_UPLOAD_DIR` setting (thanks to Bo Peng)
- Issue 267: add drop area (thanks to Bo Peng)
- Issue 275: show size of uploaded files (thanks to Bo Peng)
- Issue 278: allow the addition of placeholder files (thanks to Bo Peng)
- Issue 280: remove option `FILE_FORM_FILE_STORAGE`

- Issue 237: using with form set (thanks to Juan Carlos Carvajal)
- Issue 259: include uncompressed js
- Issue 260: correctly use formset prefix (thanks to Gzuba)
- Issue 261: fix default for `FILE_FORM_UPLOAD_DIR` (thanks to Gzuba)