Ethernet_ArduinoUNO_webserver: Added configurable MAC & IP - stored in EEPROM memory

Change IP:
http://192.168.0.109:1235/?par=0&ip1=192&ip2=168&ip3=0&ip4=108

Change MAC:
http://192.168.0.109:1235/?par=0&mac1=52&mac2=53&mac3=54&mac4=55&mac5=56&mac6=57

where 192.168.0.109 is current IP from eprom and 1235 is current port from EEPROM