Adjust CivetCombiner view code

[prioux]

The two view files for CivetCombiner crash abominably when the Combiner was created directly from a Civet's form.

That's because the view files still only expect the task's inputs to be IDs to files (CivetOutputs), but internally the task
supports providing no file ID but providing the IDs of Civet tasks instead; then it fetches the IDs from the tasks
(presumably, the task created these CivetOutputs).

When a user tries to VIEW the CivetCombiner or EDIT a CivetCombiner, it fails.