Revert "Add support for setting shard_index instead of shard_num"
Revert "Add support for setting shard_index instead of shard_num"

This reverts commit ebd5a8b7a152607af390f4f5bbc99e81c801dc9d.

berkmancenter/mediacloud,berkmancenter/mediacloud,berkmancenter/mediacloud,berkmancenter/mediacloud,berkmancenter/mediacloud