Command line example

It would be nice to have a command line based example in the QtSerialPort module. Reasoning is behind, if you have an embedded board like Panda, Beagle or RaspBerry, you might use only ssh or the native serial port for connection and compiling projects on the board. As such, you do not have for instance HDMI and so forth connection available. It would be still nice to run an example for the QtSerialPort example how to enumerate the devices like the current enumerator example does.

Also, I have an ssh access to a remote Mac PC on my friend machine, in which case I could also benefit out of such a simple example.