This example serves a "hello world" on a WLAN and a SoftAP at the same
time.
The SoftAP allow you to configure WLAN parameters at run time. They are
not setup in the sketch but saved on EEPROM.
This is a captive portal because through the softAP it will redirect any
http request to http://192.168.4.1/, served by the ESP8266 itself
