[Fix #123] Add Select Objects by Field query

[kgibm]

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Fixes #123 by adding a new Select Objects by Field query. Given a set of selected objects and a field parameter, resolve the field for every selected object (supports field nesting) and then return the unique object set (if any).

All tests pass locally.

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[kgibm]

The ECA check failed. It looks like it's because https://accounts.eclipse.org is down. Waiting for that to come back up.

[kgibm]

@jasonk000 or @krumts: if one of you can please review when you have a chance, thanks!