Hovering over a field should display CWL doc + child fields

[ghost]

When I code I often find myself referring to the specification to understand what fields are available and what they mean. e.g. I have to often look up if glob is part of CommandOutputParameter or a part of the outputBinding field.

It would be a great coding aid to be able to hover over a node and see the sibling fields of the inferred parent type and the documentation for each of the sibling fields. It is also good to be able to to see the allowed types for the value of the field.