77eae04bcf
New Snap Store policy requires *-files interface plugs be named in a specific name. Fixes #241. Refer-to: The personal-files interface - doc - snapcraft.io <https://forum.snapcraft.io/t/the-personal-files-interface/9357> Refer-to: The system-files interface - doc - snapcraft.io <https://forum.snapcraft.io/t/the-system-files-interface/9358> Signed-off-by: 林博仁(Buo-ren Lin) <Buo.Ren.Lin@gmail.com>