client: selection: enable selection of link via 0 depth selection of both nodes; resolve #393

shift selection still works, but now it's a bit not obvious when you
shift select a link:
- it acts as inverting the source and destination node.
- an alternative could be to special case for both or single or none of
  the nodes already selected
- a correct fix would be to track separately the nodes and links
  selection states. Right now we only have a nodes selection state
  (array of root nodes, the ones the user selected, and array of
  selected nodes, the ones we highlight as such).

0 files changed, 0 insertions, 0 deletions