Fix/Create judges GUI

[kev-the-dev]

The 2018 task description 5.4 mandates that we need a graphical display for the results of scan the code. we have a previous version of this navigator_judges_gui made for the 2016 challenge that is a starting point but likely will not work with the new system.

[kev-the-dev]

@BSpwr note you may find it easier to implement this as an rqt plugin rather than a standalone program. You can find an example of this with the navigator_gui package.