RFC: getting rid of oldnfs

[Rick Macklem]

Someone just pinged me on this and I figured I should
bring it up.

1 - Is anyone out there still using oldnfs due to unresolved
    problems with the new one? (I am not aware of any outstanding
    issues in the new nfs that don't exist in the oldnfs.)
2 - Does anyone see a problem with getting rid of oldnfs for
    FreebSD-11?
3 - If I get rid of it in -head, I can do it either in mid-December
    or mid-April. (I can't do commits during the winter.)
    Does anyone have a rough idea when the 11.0 release cycle will
    start, so I can choose which of the above would be preferable?
    (I figured I'd wait until after the last 10.n release that happens
     before 11.0, since it will be easier to MFC before the removal of
     oldnfs.)

Thanks in advance for any comments, rick
ps: John, I've cc'd you since I thought you are the guy most likely to
    need to do commits/MFCs to oldnfs.