Show project imports

This extension shows the imports of a CPS project in the solution explorer.

The imports are shown in a hierarchical fashion that indicates the nested nature of the imports; the imports shown under the 'Imports' node are directly imported by the project (mentioned in the project file) while those  shown under other import nodes are imported in the project via those imports.

In addition, the project capabilities defined in each import is also shown, thus helping the user determine the origin of the capabilities provided by a project.