Create map widget

[superdan-t]

• Make a map widget similar to the one in the old base station.

• It can be drawn using NanoVG functions

  • The NVGcontext is provided in the call to the draw function
  • I will create some starter code since we're still finding our way around NanoGUI

• Short term requirements:

  • Plot the base station's position and the rover's position
  • Allow setting the map scale (with a function
  • Draw grid lines
  • Center the view around the rover

• Later goals (after first PR):

  • Plot the history of the rover's position
  • Support loading an aerial image as the background

[superdan-t]

I am closing all issues related specifically to the 2022 Base Station due to our decision to reimplement using new GUI tools.