Add datasets to dag graph

[bbovenzi]

Add datasets as upstream and downstream nodes in the DAG graph.

Make it easier to visualize what a DAG is connected to. And provide a tooltip to jump over to that dataset to see what else it connects to. This makes it easier to jump back and forth between dag view and a dataset view.

Zoomed out:

After this:

• we could add the relevant dataset events to a Dataset node too. Perhaps even in both the dataset and dag graphs and we can share the node components between the two graphs.
• We can add trigger rules to the tooltip for dataset-and-timetable or any/all conditions

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[potiuk]

Not sure about the javascript code but it definitely looks good.

[dirrao]

@bbovenzi
Nice work. I believe this is for task view not dag view?

[bbovenzi]

@bbovenzi Nice work. I believe this is for task view not dag view?

Nope. For the whole dag. The example dag had only a single task.