* Add checks when serializing * Add default _estimateSize to generic inputs * Fix multisig size estimation * Change _addOutput to addOutput * Add addInput and using that internally * Split `getFee` out from `_updateChangeOutput`
* Allow `Script#add` to add a Script causing concatenation of opcodes * Add `Script#equals` to compare scripts * Add `Script#fromAddress` * Drop `_payTo` methods * Add `Script.buildP2SHMultisigIn` Greatly simplifying the internal transaction object