Ability to take screenshots

[WouterVRompaey]

It would be usefull to have a function to take a screenshot,

Workaround for the moment is doing like this:
bashCommand = ['lxi', 'screenshot', '--address', ip, filename]
process = subprocess.Popen(bashCommand, stdout=subprocess.PIPE)

[lundmar]

@WouterVRompaey When I created liblxi I intended it to mainly offer the communications protocols used by lxi instruments. Adding the screenshot feature could be done but I'm currently a bit undecided on that point.