Add bulk task endpoints.
Add bulk task endpoints.

mrpau/kolibri,learningequality/kolibri,indirectlylit/kolibri,indirectlylit/kolibri,learningequality/kolibri,mrpau/kolibri,indirectlylit/kolibri,mrpau/kolibri,learningequality/kolibri,mrpau/kolibri,indirectlylit/kolibri,learningequality/kolibri