command api: sync stdout and parse addresses parameter from json for monitor commands on CLI
added pubkeys_to_p2sh_multisig_address and tests
added redeem_script to return value in pubkeys_to_p2sh_multisig_address
use testnet url for tx relay example

so it is consistent with the rest of the transaction example
freeze time in tests
TxBuilder::sign_input now allows missing keys in multisig and p2sh_multisig
add support for multisig signers to sign seperately
Added error message when keys missing