Add a way to forget all of the wifi details

[amcewen]

If you accidentally get a set of WiFi credentials configured that don't work (maybe there's a captive portal, for example), then there's no way to tell the box to forget those details when you try to tell it the correct credentials.

Maybe the WiFi config page could have a "forget all the networks I know about" link to let you reset it if you're having problems...

[george08]

1. Show list of all wifi networks the Box knows about; can we also show network names that we couldn't connect to?
2. Add link to "forget" one, or all of them
3. Add link from "main wifi details page" to Advanced Wifi config

[amcewen]

Moved to new repo