Pending put leaks when the entity is not found in DB

When the entity is not found in DB, the registerForPendingPut is not followed by putFromLoad which should remove this pending put record. When the non-existing entry is not invalidated, the pending put can't be removed but by expiration - however, if these loads are executed more often than is the maxIdle timeout (by default 60s), the PendingPutMap grows beyond limits.