gather_sales_report_data is not returning accurate data

[Natalia Bidart]

gather_sales_report_data, when called with isv_id == -1, is returning info for only those ISV who have at least one app published at the time of the query. This is filtering out all those ISV who had an app published during the requested period, but that may not be published by the time of the query.

On the other hand, for a given ISV, the query:

    134 apps = Application.objects.with_purchases_in_months_or_published(
    135 start, end)

may return apps that are published right now but were not published during the requested period [start, end]. This can lead to including in the report apps that had no sells at all, and that were not published during the period of interest.

One possible solution to fix the first issue is make use of the app transition logs to track down the state of a given app in a given period, to ensure we're only reporting about Published apps for the requested [start, end] interval.