Display scope/net types in net hierarchy view

[jbush001]

There is a feature in the VCD format (and probably formats) to indicate element types. In IEEE 1364-2001:

• 18.2.3.4 allows specifying module types for $scope: module task function begin fork
• 18.2.3.8 allows specifying variable types. Tools like verilator support what appear to be non-standard types like 'port'.

This information could be used to display a different icon in the tree view.