Find a general fix for 0 ID in new item notifications being sent

[hhyyrylainen]

When GetNotifications is called for a new item, the Id may be 0 still

There's now a workaround in DataPage that finds the next expected ID and multiplies that by 10 to avoid key conflicts but this doesn't make updating items really work

[hhyyrylainen]

The workaround is to put NewItemRequiresFullReFetch = true; in the page using data that has this limitation so that a full re-fetch is triggered instead for the new data.