Add interactive functionality for diagrams exported to SVG, and display all nodes and connections on a line.

[diguage]

Is your feature request related to a problem? Please describe.

#930 added support for interactive event. It focuses on a node and its edges in a complex diagram, but it is not possible to display all nodes and connections on a line.

Describe the solution you'd like

Add new option: svginteractivedepth <Num>: 1 is the default value, display a node and its edges; 2 means displaying the upper and lower levels of nodes, and so on.

Describe alternatives you've considered
No

Additional context

The example:

jquery.graphviz.svg.zip