Our strategy of searching for a english string to determine if
monero_wallet_rpc is ready is not compatible with languages other than
english. Instead we assume the monero rpc is ready if it has stopped
writing to stdout. We make a json rpc request to confirm this. A better
solution would have been to configure the monero_wallet_rpc to always
output in english but there is not command line argument to configure
the language.
Closes#353.