Wallet: remove superfluous false parameter

This parameter is unnecessary.
The use of `false` causes the default parameter to be used instead; even though the absence of such would also cause said behaviour to occur.
message: add missing test for Address
Transaction: remove untested (and broken) functionality
ecdsa: add invalid test fixtures for recoverPubKey
ecdsa: amend recoverPubKey SEC comments
ecdsa: add more extensive tests for recoverPubKey