#27 use vertical axis for separate design projects

[Latha Serevi]

For some users, it will be painful that the current usage model is "one wikitree, one design project". Proposal: use the vertical axis for separate design projects -- completely separate canopies. In the new model, there would be a "current canopy" chosen from the designs stacked vertically above the tree, and indicated with a box similar to the "current leaf" box. Changing designs by clicking another design on the vertical stack, would de-rez the old canopy and rez the chosen design's canopy.