Code review comment for ~craftyjon/kicad:bus_upgrades_merge

After working with this for a day, I found a few issues although I haven't tested out the new unfolding/naming paradigm. This is just trying to work with it as before.

- Hierarchical sheets are not handled correctly. 1 layer deep and the net loses its sheet prefix. 2 layers deep and the net loses the prefix 1 before the net name.

e.g. /Sheet1/Net1 becomes /Net1 and /Sheet1/Sheet2/Net2 becomes /Sheet1/Net2

Some of this can be seen if you open PIC programmer demo and update from the schematic. All tracks (most?) are disconnected

- Undo/Redo doesn't work correctly when placing wires or busses in eeschema. Place a wire with multiple bends and then undo, you will often end up with a single wire segment remaining that doesn't live in the undo/redo stack.