This commit makes a large number of minor changes concerning API usage
within the deamon to match the latest version on the upstream btcsuite
libraries.
The major changes are the switch from wire.ShaHash to chainhash.Hash,
and that wire.NewMsgTx() now takes a paramter indicating the version of
the transaction to be created.
Moved transaction states from in-memory maps to persistent BoltDB
buckets. This allows channel force closes to operate reliably if the
daemon is shut down and restarted at any point during the forced
channel closure process.