PaymentChannelClient support for encrypted wallets. 

If a wallet is encrypted, we found that payment channels do not work. This solution aims to make it possible for a user to provide password when a channel is created and when the channel is incremented. This proposal only enables client wallets to be encrypted.
When I got an error the getMessage() in my case returned "null", so there was no stacktrace and no message. (The second row is there only to make sure the stacktrace is not eaten)