Miscellaneous fixes
This MR contains a group of unrelated commits that fixes some issues. The "most important" changes are:
- When a picture is saved, it was saved into
.pdfand.svg. I changed.svgback to.pngbecause.svgdoes not work well with PowerPoint. - I added a processing
edges_at_least_3_planesjust after the embedding, which allows to consider that a track is genuine only if it has 3 hits on 3 different planes.