Suggestion: allow navigation via railroad diagram view

[zspitz]

Allow navigating to a child node in the railroad diagram view, from the railroad diagram view.

I think the natural interaction choice would be to click on the node.

Perhaps this could be implemented by passing some sort of dummy URL as the second parameter to the JS library used to generate the diagrams, and registering a global handler for this dummy URL to navigate to the appropriate node.

[mike-lischke]

This is related to #24. Requires a rewrite of the railroad diagram script.