* make trace logging "core-pushes" model, to a sink installed by the frontend. This sink can go straight to the disk without wasting memory if that's what the Trace Logger tool has selected; or the Trace Logger will buffer it if it needs to. Formerly, we had a "core-pushes-to-buffer" and "client-pulls-once-per-frame" which necessarily caused huge buffers no matter what was going on.
Now fully use comparer class. That saves memory and offer extensibility
ItemCount property obsolete => Moved to Count property (which did the same thing)
Moved ConfigPersistAttribute.cs, IToolForm.cs, IToolFormAutoConfig.cs back to common