* Implement collapsing component hierarchy.
* Save screen when adding new components.
* Allow creation of nested child components.
* Fix level-based indentation of hierarchy.
* Rename updateComponentProps to setComponentProps
* Save layout information to the disk.
* Cleanup: switch to autosubscriptions to prevent memory leaks, remove unused imports.
* Remove unused css.
* Fix incorrect subscription.
Martin McKeaveney
pngwn
Michael Shanks