More modeler plugin refactoring.

* Move network interface modeling logic from being duplicated in WinOS and
  and ClusterOS modeler plugins into a standalone Interfaces modeler plugin.
* Add support for shell and PowerShell commands to WinRMPlugin.
* Add support for alternative namespaces for WQL queries.
* Eliminate os/teaminterfaces relationship.
* Model team interfaces into the regular os/interfaces relationship.

Fixes ZEN-9007, ZEN-9008.