Broaden dependency version constraints for plugins

* In order to support both kepler and luna TPs, it is necessary to widen
  the min/max version constraints on certain plugins.
Fixes json lib plugin maven errors

* json.lib should not have a maven nature since this just generates m2e
  errors in eclipse

* Corrects the dependent jar name in the plugin to stop the plugin being
  completely rebuilt everytime a workspace build is initiated.
TEIDDES-2333: Removes hte ControlledPopupMenuExtender

* Class uses eclipse internal API for generating entries for context menus
  which are irrelevant to the purpose of the parent editor.
Merge pull request #415 from phantomjinx/8.6.x

8.6.x