DataSyncService ignores removal of non-existent keys.

Fixed removing data in DataSyncService.

Bugfix for duplicate node/link insertions. Performance improvements in DataSyncService syncNodeData and syncLinkData

Use splice instead of filter in DataSyncService.syncNode/LinkData to avoid immer errors. New build process using ng-packager since build-ng-packagr was deprecated.

Update modelData before node / link data in Diagram / Palette initialization in case of bindings dependent on modelData

Update modelData before node / link data in Diagram / Palette initialization in case of node / link bindings dependent on modelData

Adds DiagramComponent.clear method for treating next state update as Diagram reinitialization

Adds DiagramComponent.clear method for treating next state update as Diagram reinitialization in 1.x branch

Readme.md contains a migration guide for version 1.x -> Version 2

Removes unneeded calls to layoutDiagram in ngAfterViewInit lifecycle hooks in DiagramComponent and PaletteComponent