1. Replaced IP65 Ethernet drivers with Contiki drivers.

* CS8900A
The Contiki driver allows to adjust the chip base addr at runtime (which  allows to support different slots in the Apple II) and removes received frames from the chip if there's no room to send frames.

* LAN91C96
The Contiki driver was used by IP65 more or less unchanged in the first place.

* W5100
The Contiki driver allows to adjust the chip base addr at runtime (which  allows to support different slots in the Apple II) and stays clear from the W5100 hybrid mode. It presumes a fully functional W5100 register auto-increment and pre-calculates necessary W5100 frame buffer wrap-arounds and thus achieves the maximal 6502 <-> W5100 transfer speed.