Import FreeBSD's "newnfs" nfs client and server code. This contains
nfsv4 as well as new implementations of nfsv3 and nfsv2.

This import is from tonight's FreeBSD head and is unchanged from there
except for automated munging of rcsids, rearranging of paths, and an
autogenerated files.* file that might or might not be syntactically
valid. (I will check in the script that does this shortly.)

There is not the slightest chance this will configure yet, let alone
compile or run.