This commit restructures the HTTP based protocol negotiation that `rippled`
executes and introduces support for negotiation of compression for peer
links which, if implemented, should result in significant bandwidth savings
for some server roles.
This commit also introduces the new `[network_id]` configuration option
that administrators can use to specify which network the server is part of
and intends to join. This makes it possible for servers from different
networks to drop the link early.
The changeset also improves the log messages generated when negotiation
of a peer link upgrade fails. In the past, no useful information would
be logged, making it more difficult for admins to troubleshoot errors.
This commit also fixes RIPD-237 and RIPD-451
This commit allows server operators to reserve slots for specific
peers (identified by the peer's public node identity) and to make
changes to the reservations while the server is operating.
This commit closes#2938
