Provide more direct method fo navigating to Data Source from Graph

[TheWitness]

Describe the bug

When you are editing a Graph and wish to navigate to the Data Source(s), or editing Data Sources and wish to navigate to the Cacti Graph or Graphs it is very cumbersome.

Expected behavior

Make Cacti easier to use.

[TheWitness]

This resolution provides a partial fix to #4172

[bernisys]

That one is very helpful indeed, thanks for adding this! :)