With this change, transactions created via craftSweepTx will be
standard. Previously, p2wsh/p2pkh scripts passed in via SendCoins would
be weighted as p2wpkh scripts. With a feerate of 1 sat/vbyte,
transactions returned would be non-standard. Luckily, the critical
sweeper subsystem only used p2wpkh scripts so this only affected
callers from the rpcserver.
Also added is an integration test that fails if SendCoins manages
to generate a non-standard transaction. All script types are now
accounted for in getWeightEstimate, which now errors if an unknown
script type is passed in.
