(PR#1404). Things to be noted:
- all IP addresses are now `struct in_addr's.
- the function rarp_getipaddress() no longer return `myip'; in stead
it returns -1 on failure (errno set), 0 on success. `myip' is set
as a size-effect.
* 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.
