Diagram editor should preview selected node (net or diagram) on click

[wires]

Preview of nodes in diagram editor

When nothing is selected, show the diagram "fullpage"

When a node is selected, slide open a side panel that shows a preview of the selected node (either a diagram or a net) on the top and property table at the bottom

bonus If the node is a leaf (ie. petrinet) then we want to show an unfolding of the net (as a graph) instead of the property table.

[epost]

• [x] DiagramEditor should handle clicks on operators
  • [x] Emit (H.raise) these as a Msg from the DiagramEditor.ui component.
  • [x] In Studio, do something with these Msgs, eg log them.
  • [x] Show a selected petri net node.
  • [ ] Show a selected diagram node. (Moved to separate issue #117.)
  • [x] Store selected operator in diagram editor component state.
  • [x] Visually highlight selected operator.
• [x] Route
  • [x] don't store diagrams or nets inside the route.
  • [x] Match routes using a normal Eq instance instead of hacky routesObjNameEq.
  • [x] Instead, store ids instead and then do a lookup whenever we need to render one.
  • [x] Parameterise RouteF in p, n, d, for project, net, diagram, so we can use it as either a pointer to some object, or the actual ('reified') data.
  • [x] Studio state should store the 'current' net/diagram/diagram&net in terms of a RouteF Project DiagramInfo NetInfo

[wires]

sick :)