Added
* `SingletonMetaClass` for Python 3+.
* `SingletonMetaClass` for IronPython 2.7.
* `App` singleton as main entry point.
* `Scene` singleton for managing UI objects.
* `Session` singleton for managing additional session data.
* `Scene.record`, `Scene.undo`, `Scene.redo` based on copy/deepcopy.
* `Scene.save`, `Scene.saveas`, `Scene.load` based on pickle.
* `Session.record`, `Session.undo`, `Session.redo` based on JSON dumps/loads.
* `Session.save`, `Session.saveas`, `Session.load` based on JSON dump/load.
* `App.record`, `App.undo`, `App.redo` combining scene and session.
* `App.save`, `App.saveas`, `App.load` combining scene and session.
* `Object` pluggable as context-aware UI wrapper for data and artist, with support for copy/deepcopy and pickle dump/load.
* `MeshObject` as base for context-aware UI wrapper for mesh data and artist.
* `NetworkObject` as base for context-aware UI wrapper for network data and artist.
* `VolMeshObject` as base for context-aware UI wrapper for volmesh data and artist.
* `RhinoObject` as plugin for `Object` in the Rhino context.
* `RhinoMeshObject` as plugin for `MeshObject` in the Rhino context.
* `RhinoNetworkObject` as plugin for `NetworkObject` in the Rhino context.
* `RhinoVolMeshObject` as plugin for `VolMeshObject` in the Rhino context.
Changed
Removed