Work for TS 54

[reshmabidikar]

Work for https://github.com/killbill/technical-support/issues/54 (Round 1). Includes changes to some of the reports under src/main/resources/reports.

Some notes:

• I have not moved the reports to the top-level reports directory as part of this PR in order to make it easy to compare the changes. I will do this once we finalize all the reports
• For some of the reports, I've added sample data, I think we should do this for all the reports

Some notes about the queries:

• Monthly Active Subscriptions - The query in the stored procedure looked wrong, so I've modified it to just insert the data from the view into the table
• Daily Refunds Value - Query is modified to use the absolute value of the converted_invoice_amount_refunded column instead of the converted_amount column
• Conversions - Earlier, this report was using a temporary table. I've changed the query to avoid using a temporary table and to use a view (to keep this report consistent with the other reports).
• Daily Payments Value - Earlier, this report used 2 views. I made modifications to use a single view to keep this consistent with the other reports