Add scanning functionality

[DAT4]

It could be nice to be able to list the nearby stations in the range of the wifi interface.

[bogdanciuca]

Am also very interested in this feature.

[lukas-mbag]

Same for me. See also the comment on Pull-Request #29

[flotter]

@mdlayher I would like to help getting AP scanning support working in this package. I have not studied the existing PRs in detail yet, but what would you like to see to move AP scanning support forward? I am happy to help with the effort. @SuperQ I see the last PR was approved by you. I am not sure who maintains this package, but if you could advise / help, that would be awesome!

[SuperQ]

Fixed in #117