[1.5.x] Corrected minor typos in FileUploadHandler.receive_data_chunk docs.
[1.5.x] Corrected minor typos in FileUploadHandler.receive_data_chunk docs.

Backport of 6466a08 from master.

alx-eu/django,bliti/django-nonrel-1.5,imtapps/django-imt-fork,ccn-2m/django,hasadna/django,alx-eu/django,hasadna/django,bliti/django-nonrel-1.5,hasadna/django,imtapps/django-imt-fork,imtapps/django-imt-fork,bliti/django-nonrel-1.5,alx-eu/django,alx-eu/django,ccn-2m/django,ccn-2m/django,ccn-2m/django