Add link to Launch Pad Station

[wanysteus]

solves #15

• [x] Add serial read ability to dummy_interface.ino
• [x] Add serial write ability to serialwrapper.py

What's new?

• Interface instances can send data via Serial link
• dummy_interface.ino can be used to mimic a Telemetry interface or an LPS interface
• A simple GUI lps_control.py can easily control the LPS
• The Serial device is searched for on start_read() call and not on Interface instance initialization anymore (quicker to launch)