Support objects in OutputEvent

[isidorn]

Currently when debugging node, evaluating 'global' gives a nice expandable object, but 'console.log(global)' is a giant string. An OutputEvent should be able to take a variableReference like an evaluate response.

Giving this to you @weinand to investigate and if we want to introduce it give it back gto me so I implement it on the vscode side.
Requested by @roblourens

[roblourens]

Should this be tracked in a different repo now?

[weinand]

the debug protocol addition is microsoft/vscode-debugadapter-node#79