Move the AFSCombineTokens to its own section

Occurring after the token-format section, for better readibility.

Change-Id: I78fe1663f02fce4acc21dfb74d4f27bbd2a9131b
Move around "Client Tokens" and "Authenticator Data"

Try to get the bits that define application-specific rxgk pieces
earlier, and the custom AFS bits that rely on them later.
More rearrangement to come.

Change-Id: Ie7e0dc3607a8ccef3bb6f2a42f6d083c7a34f52c
Combine into server-to-server communication

Declaring fileserver support is server-to-server, and "Per-server keys"
is really talking about VL_RegisterAddrsAndKey, which is also
server-to-server.

Change-Id: I0b22bf244778bd5a78fafc8ceb2ed4d39e0756a6
Let xmllint --format loose

To correct the indentation level when moving from sections
to sub-sections and vice versa.  It's not perfect, but it helps.

In particular, xmllint likes to squash together the closing and
opening <t> elements within a list environment, which makes
really long lines.  I went through and fixed those manually.
Some of them were previously broken from the prior xmllint run,
and I hadn't run into them yet.

Change-Id: Ie66ed51600ae770edd50aaefd8a405cfb5251345
Mention that the opaques are implementation-defined

In the GSSNegotiate loop.

Change-Id: I82d46a61b32845406b738c146137c6a020a7d94e
Change the section heading to Cache Manager Tokens

"Client Tokens" is pretty ambiguous.

Change-Id: I6228af4ae76ec3edc5544207d76974a1191b342d
Change section heading to "Registering Per Server Keys"

The text doesn't talk about how to use them, it talks about how to
set them up.

Change-Id: I48b2e5b7fb404c66fe4eebb66940b315ad3c9c38