Support creating PDFs for each invoice

[rawdaGastan]

Describe the solution you'd like

Creating a PDF for each invoice and send it to frontend and through mail

[rawdaGastan]

WIP:

• fix right alignment
• fix items that overflow in the page

[rawdaGastan]

Work in progress:

• send emails with the invoice
• save in DB and serve files

Completed

• create invoices in pdf
• Fix right alignment
• Fix overflow

[rawdaGastan]

Work completed

• invoices are available as PDFs
• PDFs is created per invoice
• An endpoint is available to download invoice PDF
• PDF file bytes is stored in the DB
• PDFs is sent when created in an email and with every reminder mail