* Allow configuration of Ethernet PHY clock source
Refer to https://github.com/espressif/esp-idf/pull/1127
The internal APLL can be used to generate the 50MHz clock for the internal EMAC and the external Ethernet PHY.
The clock can either be input on GPIO0 (as before) or output on GPIO0, GPIO16 or GPIO17 (only GPIO17 extensively tested).
New example available.

* Allow configuration of Ethernet PHY clock source
Refer to https://github.com/espressif/esp-idf/pull/1127
The internal APLL can be used to generate the 50MHz clock for the internal EMAC and the external Ethernet PHY.
The clock can either be input on GPIO0 (as before) or output on GPIO0, GPIO16 or GPIO17 (only GPIO17 extensively tested).
New example available.

* little fix to WiFiSTA.cpp

Now SmartConfig works! Tested on ESP32

* little fix to WiFiSTA.cpp

Now SmartConfig works! Tested on ESP32

Missed definition

Fixes: https://github.com/espressif/arduino-esp32/issues/749

Works even when single core mode is selected

Fixes: https://github.com/espressif/arduino-esp32/issues/654

Helps in cases where Event Info is needed (WPS and others)

Fixes: https://github.com/espressif/arduino-esp32/issues/553

* Change disconnect function

Current implementation does not disconnect the WiFi. Use of `esp_wifi_disconnect()` does.

* Update WiFiSTA.cpp

put back the clear ssid + password
remove the duplicate `esp_wifi_set_config(WIFI_IF_STA, &conf);`

send() can return a value > 0 but less than size indicating it was able to accept some of the data in buffer. The caller must try again after updating the buffer pointer and size remaining.

Connected to: https://github.com/espressif/arduino-esp32/issues/400

Required for WebServer and/or DNSServer libraries

Implement methods from ESP8266WiFiClient but use sockets API.

* Update WiFiAP.cpp

set from code the maximum number of clients to smaller than 4 (in my case i must allow only one client at a time)

* Update WiFiAP.h

* Update WiFiAP.cpp

* Update WiFiAP.cpp

* Create WiFiAP.cpp

Fixes: https://github.com/espressif/arduino-esp32/issues/400

Fixes: https://github.com/espressif/arduino-esp32/issues/391

WiFiTelnetToSerial is also a test for hasClient().

Fixes: https://github.com/espressif/arduino-esp32/issues/373

This needs proper testing!
Fixes: https://github.com/espressif/arduino-esp32/issues/353

- call esp_wifi_start()
- separate tcp initialization to prepare for Ethernet
- setup dhcp addresses when using custom IP config for SoftAP

Thanks @miomir1981

* Add setNoDelay and getNoDelay to WiFiServer class

* Remote TCP disconnect not detected

Fixes: https://github.com/espressif/arduino-esp32/issues/329

Fixes: https://github.com/espressif/arduino-esp32/issues/304

Thanks @jliegner :)

thans @martinayotte

Should Fix: https://github.com/espressif/arduino-esp32/issues/234

Fixes: https://github.com/espressif/arduino-esp32/issues/275

Fixes: https://github.com/espressif/arduino-esp32/issues/263

Actually WiFiMulti is not working due some functions haven't equal comportment of ESP8266
Replace status == WL_DISCONNECTED => status != WL_CONNECTED
Replace scanComplete() => scanNetworks()

Maybe is more interesting, for keep the maximum compatibility, investigate why WL_DISCONNECTED and scanComplete() doesn't works in this case instead of just replace by this pull request.