MDR-6 - Improve the plugin dependency visualization utility

Brief

Utility at: https://github.com/qcadoo/qcadoo-incubator/tree/master/plugin-dependency-visualiser

Previous spec: Plugin dependency visualization utility

The code quality is pretty poor, it should be improved.

New features / changes to implement:

  • remove the group from the utilities descriptors.xml, we'll use the new group attribute which is directly in the plugin descriptors to box nodes 
  • add a plugin descriptor extractor similar to the one activated by the <archive> tag but which can work directly on a plain git repository
  • fill plugin with license=Commercial with light green color, others with light orange