dblclick to show nodes is also a click during corridor selection

[Nate-Wessel]

Given that this is already an undocumented feature, it may be best to just change the mechanism for displaying node options. One thought is to wait for a stable, non-moving mouse on the map and render nodes around that.

This could be done with a combination of onmousovers and on-leave events to figure out when the cursor has actually stopped moving on the map for a second.

Thanks @AdK0101 for bring this to my attention!

See here for ongoing parallel work on this.