Allow viewing / editing of "paid invoices" #528
Description
- Display invoice link on Transaction table
- Clicking the invoice button for that payment would take them to the invoice screen for that payment
- The amount would be filled in, but they could edit things like what it's for (eg. 1 pepperoni pizza), who they (the recipient) is, their address, same info for the customer who paid, invoice # (which we can auto-fill with the format YYYY-123, auto-inc)
- Option to save as PDF
- v2 could probably allow them to "combine" multiple payments into 1 invoice for the case when the customer pays too little initially for some reason (it would be rare but could happen at scale).
Related to #136.