Attempt to make the GSS negotiation loop correct

Describing these things is always challenging; I'm still not very happy
with this version.

Change-Id: I15ac1d7c8962aac6cd853cbcc404c55df52a8a04
Talk about acceptor principal names for GSSNegotiate

The client has to know the target principal's name; give it a
suggestion for when it knows better.
The server, however, should not specify a name, since that would
be overly restrictive.

Change-Id: I24481178aef93b40ae10097f9b76e3765431bbb0
Tweak RXGK error code descriptions

Do not restrict BAD{LEVEL,ETYPE} to the negotiation RPCs.

Change-Id: I9b581d31d342907cb6fdfbf3902a1c49137d3283
Mention non-database non-files AFS servers

E.g., bosserver, which must run a negotiation service for the
bootstrapping stage.

Change-Id: I83bb749310bf030c1f342a31d1e0e0217e249946
Revert "Mention non-database non-files AFS servers"

This reverts commit a1f731943b2522a84c1815f2f056c3f3398ce9c6.
Fixup pointer for bosservers

Change-Id: Ibc125e6cf95e4fdaff43ec06e37d126216fa8d70
Prescribe leap of faith for RegisterAddrsAndKey

Bind a GSSAPI identity to fileserver UUID, needed to authenticate
future operations on that database entry.  Also suggest periodic
rekeying per best practice on key lifetimes.

Change-Id: Idec26ee2184fd458186fcbdc4783dbea7d29b4eb
Inline VL_RegisterAddrs elements

Do not attempt to incorporate by reference a reference which does
not exist.

Change-Id: I41d725a7ef27525be2002919d04980a45d89c289