Allow users to upload single photos
Making new feature or flags requires linking an image. Ideally this is a Mapillary image, but we should allow for users to simply upload their own. This is a complex feature with the following steps:
- Add an image upload button to the Feature and Flag creation panel
- Store that image locally, or in the data base?
- Upload that image to Mapillary
- Change out the URL from the local image to the Mapillary image when it becomes available
- Delete the local image once the image is available