Skip checking for duplicate inputs when adding zerocoin txs to the wallet
Skip checking for duplicate inputs when adding zerocoin txs to the wallet

As all zerocoin transactions have inputs with tx hash 0x0, all zerocoin transactions
were marked as 'conflicted' due to having the same inputs as other transactions.

ionomy/ion,ionomy/ion,ionomy/ion,ionomy/ion,ionomy/ion,ionomy/ion