Use /author/by_ids API endpoint

[mickeyn]

Replace query sending with a call to the new API endpoint.

[coveralls]

Coverage increased (+0.2%) to 76.601% when pulling db7da2e on mickey/use_author_by_ids into 4f92ac7 on master.

[coveralls]

Coverage remained the same at 76.811% when pulling 3d64c0d on mickey/use_author_by_ids into cbb4938 on master.

[coveralls]

Coverage remained the same at 76.846% when pulling 490c3a7 on mickey/use_author_by_ids into b2f653c on master.

[coveralls]

Coverage remained the same at 76.846% when pulling 3ad9cc6 on mickey/use_author_by_ids into b2f653c on master.

[coveralls]

Coverage increased (+0.2%) to 77.081% when pulling 5604c70 on mickey/use_author_by_ids into a6a9571 on master.