remove mongodb _id property from dataset output

it makes it so much longer, as every single action in the actionQueue (which is duplicated 3 times as of now) has a bunch of extra characters associated with it.

Search the repository for the dataset output and actionQueue generation, then inspect how MongoDB documents are serialized. The work is done when each actionQueue item omits the MongoDB _id property and the resulting dataset output is shorter without changing other fields.

Written by the indexing model from the issue text.