TODO

- Check appropriate user permissions (e.g. "access contributions")
- Improve user interface when generating individual receipts
   - Also add shortcut menu action(s) for individual receipts generation
- More elegant and powerful approach for receipts batch generation: based on a custom search and search results action
- Associate receipts more directly with the contributions they belong to: possibly integrating with the upstream "receipt" functionality, and/or using activities
   - This should also allow for some straightforward method for undoing a complete receipts batch run