Allow configuring hostname Esplink

[jwetzell]

Looks like right now it uses the SSID? as the default hostname. This should probably be configurable and potentially a better default than the SSID as that doesn't really make sense.

[deadprogram]

potentially a better default than the SSID as that doesn't really make sense

That is probably true. Any suggestions for a better default value?

[jwetzell]

espressif just defaults to "espressif" I'm pretty sure you could default to "espradio" or something. I'd have to look at what kind of information is available at that point I've seen some things default to something with the MAC in it as well.