SIRS Knowledge Source [new translator]

New translator for SIRS Knowledge Source, a ProQuest K-12 database
(Note: this only covers Knowledge Source, not SIRS Discoverer or SIRS Decades)
Do you need that itemType check? We don't currently have 'place' for document, but we will almost certainly get a full array of fields for document at which point this would start working. Just let Zotero filter out invalid fields.