* Remove unnecessary MY_IP_RENEWAL_INTERVAL*
Ethernet.maintain already checks when we need to renew, based on
the lease time given by the DHCP server.
https://www.arduino.cc/en/Reference/EthernetMaintain recommends
"just call it on every loop() invocation" so there is no
need for us to keep a separate timer.
* Remove call to _w5100_spi_en
This function doesn't enable SPI, so it should not
disable it either. Let calling functions handle SPI
enable/disable.
- Fix UDP send
- Add a default value for MY_IP_GATEWAY_ADDRESS and
MY_IP_SUBNET_ADDRESS, making them optional when using MY_IP_ADDRESS
- Add support for MY_IP_GATEWAY_ADDRESS and MY_IP_SUBNET_ADDRESS to
W5100
Removing MY_LED_BLINKING_FEATURE, as we now are
using MY_DEFAULT_LED_xx_PIN defines to enable
LED blinking feature.
updated Gateway sketches to not refer to
MY_LED_BLINKING_FEATURE any more
fixes#562
