Is it possible to upload a receipt picture using the API? #21

What the title says: both on the web-app and the mobile-app it is possible to attach a picture to an expense, is this functionality exposed in the API? I am trying to write some scripts for personal use to automatize entry of expenses and it would be nice if I can do it all in one place.. otherwise I would need to go back into the app and update the generated expenses to add the pictures...