Full-scale trees

As I wrote yesterday in my post, leaves are now working and the tree
looks great! Try and run app.Main to see how it looks yourself.
Also in this update: Some old examples of apps (most of them aren't
currently working because of changes to the data structure) saved to
test.app.
Merge branch 'master' of https://github.com/amirsarid/TheMusiciansDream