Enhanced wifi-setup for Mycroft devices

This release is focused on the process of getting a new Mycroft device connected to the internet easily. It now walks you through the setup process "out of the box" and will also help you setup up if the connection is lost at a later time -- i.e. if the unit gets moved to another location.

NOTE: These changes apply to the ARM build, so they will also impact a generic Raspberry Pi with mycroft-core installed on it. The walkthru makes reference to the button on the top for now, but the triggering interface and terminology will move into the Enclosure in the future so custom hardware can customize it as appropriate.