Improve ReadMe

[pucciland95]

In order to improve the ReadMe, the following things should be added:

• Explain how the .yaml file works and how it should be filled.
• Create a simple example (filling the .yaml, launching the node and calling the services) with gifs as output results.
• Create a section that shows how the hardware is supposed to be connected.

Feel free to add others if you need clarification.

Niccolo