fixed default sim rows and wait for last row
prevent unusable dust from getting into utxo queue
return change after splitting utxos
make sure rand addrs are unique
added README
added unit test for utils
updated .travis.yml to run tests
refactored sim, miner into node, args
added unit tests for btcd
updated tests, added Connect method
cleanup after testing
refactored sim.go to use btcd node
re-use Node in actor and miner