transporthandler: Rewrite + New Handler

This rewrites the old transport handler to use the new ipmi handler
registration functions. It attempts to clean up the old code, by
refactoring any business logic out of the code that parses the IPMI
messages. This makes the code paths easier to understand and allows for
better code re-use.

This also gets rid of the concept of the settings change timer. Clients
expect to see their settings take effect as soon as they are set,
regardless of the "Set In Progress" flag. This means we no longer need a
cache for our network settings that are about to be set by the daemon,
and a client can hold the BMC in "Set In Progress" while it verifies
settings like other BMC implementations.

Change-Id: I5406a674f087600afdfc2c0b3adeacde10986abc
Signed-off-by: William A. Kennington III <wak@google.com>
7 files changed