Feature Request: read mission form .bin file directly

I often need to know a mission from a bin. Right not it takes three steps:
- press button "create KML+gpx" (which also creates waypoint files)
- sort through multiple waypoint files to discard the junk partial ones via notepad (see https://github.com/ArduPilot/MissionPlanner/issues/1718)
- open the rest of them one by one and see if any of them look like they match a flown mission

It would be nice if the Flight Plan page had a "load bin file" button (or was combined in existing button) that would allow selecting which of the multiple missions I want to view. That is, I'd like to load a bin and then have it offer mission 1,2,3,4,5, and then I can select 4.

Start at the Flight Plan page and trace the existing "create KML+gpx" flow that processes a .bin file. Done means a user can load one .bin file, choose among the missions it contains, and view the selected mission without manually sorting waypoint files.

Written by the indexing model from the issue text.