a) check against `my' ethernet or broadcast addresses done in
ether.c
b) changed interface to readether() to provide ethertype info
c) respond to arp requests when appropriate.
First two are clean-up. Last fixes hp300 and presumably mvme68k netboot
code.
* Fix some misused types.
* Encapsulate the protocols better.
* Rearrange the RPC stuff to work more like the kernel. (Needs more work.)
* Remove a bunch of extra hair when reading a file over NFS.
* Use RPCAUTH_UNIX when talking to the NFS server.
