Fix the navigation menus

[onthebreeze]

Currently we have

Tools 
 -> Extension Manager ...
 -> OpenAPI
        -> Generate Specs. 
                -> when selected then choose package or diagram 
                -> then choose JSON & YML, JSON, YML, JSON Schema
        -> Test package or diagram
                -> choose package or diagram
        -> Test entire project
        -> extension version : 0.4.0-rc4
        -> about extension
                  -> some data about the extension - including a DIFFERENT version to the one above
 -> JSON-LD
        -> Generate
              -> choose package
 -> Model Interchange
        -> Import
              -> choose file
        -> Export
              -> choose package

it's really a mess. should be more like:

Tools 
 -> Extension Manager ...
 -> JSON Tools
      -> Import JSON-LD Vocabulary -> for now "this feature is coming soon". later (prompt for file or URL)
      -> Export JSON-LD Vocabulary -> (prompt for package or diagram)
      -> Import OpenAPI Specification -> for now "this feature is coming soon". later (prompt for file or URL)
      -> Export OpenAPI Specification -> (prompt for package or diagram)
      -> Import JSON Schema -> for now "this feature is coming soon". later (prompt for file or URL)
      -> Export JSON Schema -> (prompt for package or diagram)
      -> User Guide for this extension -> link to github pages
      -> About this extension -> popup details including correct version & release date.

in all of the import/export options, checkbox "test run only").

and we can totally get rid of the model interchange extension as the JSON-LD import/export will replace it.

thoughts?