Select receipt image size, resolution, and amount for PDF Reports

There should be an option to choose the size of the image attached to the PDF Expense reports generated. Currently, small (illegible) images are shown in the PDF as a preview with a web link to a full size image. We should have the option to choose a full size image to be included in the PDF.

Thanks in advance!
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Ideally:
- Be able to select the amount of receipts per page, or the image size of the receipt. Image should be a high enough resolution so that the user doesn't have to click "View Receipt" to read it.
- Option to convert PDF to black & white to reduce file size

tags: adjust receipt image, change image size, custom receipt image, receipt number