[FIX] Incorrectly reported Unconfirmed coins in wallet for alt coin amounts

On coins with a number other than 120 as the required amount of network confirmations, sometime the wallets incorrectly report the number of unconfirmed coins due to blockupdate only updating a blocks confirmation based on the config entry of ['confirmations']. I think it should continue to update the number of confirmations based on ['network_confirmations']. This way, when classes/block.class.php searched for unconfirmed blocks, it will find all blocks with less than ['network_confirmations'] blocks. Assuming the config file is correct, this should give the correct amount of Unconfirmed currency in your wallet. This is my first code commit, so I apologize if I have done this incorrectly.