Update the profileViewer demo to use the new tree api
Update the profileViewer demo to use the new tree api

It's a bit shorter and clearer.
This was a good workout for the TreeStore impl, it exposed one segfault
bug (the treeStoreRemove [] one) and the problem with inserting subtrees
not updating the view properly.

darcs-hash:20061224011102-b4c10-223010026d71e5f10c24890f1ef4bcad6a7de7c1.gz

thiagoarrais/gtk2hs,thiagoarrais/gtk2hs,thiagoarrais/gtk2hs