Remove ancient FlyMine property from mine-structure.
Remove ancient FlyMine property from mine-structure.



Former-commit-id: 226cf837a0c72d8efcc319f74959c296b186ea1f
julie-sullivan/phytomine,julie-sullivan/phytomine,julie-sullivan/phytomine,julie-sullivan/phytomine,julie-sullivan/phytomine,julie-sullivan/phytomine,julie-sullivan/phytomine