Coin control (experimental)

I managed to merge some Bitcoin and Yacoin code into Peerunity to add the coin control features.

The list of inputs seems to be displayed correctly in the coin control dialog (when the option is selected in the option dialog).

However, I have not tried to make a transaction yet, as I don't have any testnet coins. I tried the testnet peercoin faucet, but my IP is also a Tor exit node, and the faucet refuses to send testnet coins to a Tor exit node. So if one of you guys could send a few a those to mw2pj33HMhRfRkKtceHcyKpPiGYkPdD4SM, I would be able to make some tests right away instead of mining and waiting for 520 blocks...

After merging the coin control features, I noted that some address labels are missing in the transaction list, so there are some bugs to correct for sure.
Maybe we could put this pull request in a dedicated branch for everyone to be able to test and correct it...