much better working load / save; though there is still complexity in the double-tree issue of the dynatree cloning the Folder objects; we should maybe just use the real dyna tree structure...
add a hook to easily get the root tree node
use the underlying treeNode model that the tree widget creates and moves around with drag and drop; rather than trying to keep it in sync with another tree structure to simplify the code and avoid 2 lots of models causing confusion #228
fixed up the loading and saving of expressions #228
only use 'from' as first endpoint in a route