Function install 

pub fn install(
    store: &Rc<dyn DurableStore>,
    package: &str,
    room: &str,
    doc: &mut AutoCommit,
) -> Result<RecordCheckout, TransferError>

Make doc (from rehome) a record of package in room. Refuses to overwrite anything already stored under its id.

Errors

A document not scoped to room, an occupied id, or storage failure.