Mesh-wide map visualization

[selankon]

With the following layers:

• Signal noise ratio for every link in the mesh network
• Reachable and unreachable nodes
• Sources of interference
• Hidden node problems

Depending PR

libremesh/lime-packages#1038

[selankon]

A mocked implementation is done here

https://github.com/selankon/lime-app/tree/feature/implement_mesh_wide

This is not PR yet awaiting the work on lime packages. Some screenshots