added 'Ring' Layer
fixed ring Collider
added snapping to ring in WorldCursor

Added scripts for generating circle-, cone and torus shaped meshes
Added fact visualisation for CircleFact as torus
Moved CircleSegmentGenerator under MeshGenerator

+Doygen for most of Assets/Scripts/InteractionEngine/FactHandling/* and Gadget.cs +Bug fixes for saving/loading fuctionalities of Stages

+MainMenue: Create new Stage files via UI +StageStatic: differentiate between developing and playing

+Added Scenes: MainMenue, LoadingScreen +Stage: Save-Load fuctionality +Sorted Prefabs and Scripts Folder

+FactOrganizer: hid FactDict +Facts: re-renamed URI to Id, enabled persistend, generated and compact LabelNamingSpace

+Restart: reenabled RestartLevelButton +Level: reenabled Level-completion +FactOrganizer: scetch for dynamic LevelGoals, with-> +FactComparer +ShinyThings: TODO: multiple highlited facts at once

misc: just PointerGadeget snaps on tree-roof, used 'IsApproximatelyParallel' for RayFact Equivalency