If one calls `fundrawtransaction`, the change address will be retrieved from the keypool, though, this key/address will always be returned to the pool, leading to the problem that the next `getnewaddress()` call will restult in the same key/address.

Either we remove the auto-change-address (users would need to call `getrawchangeaddress` first [current best practice anyway]) or we add a call to keep/mark a specific key/address as change (after one have sent the funded raw transaction).

Reported by @NicolasDorier on IRC.
{
    LOCK(cs_wallet);
    set<CTxDestination> result;
    BOOST_FOREACH(const PAIRTYPE(CTxDestination, CAddressBookData)& item, mapAddressBook)
    {
        const CTxDestination& address = item.first;
        const string& strName = item.second.name;
        if (strName == strAccount)
            result.insert(address);
    }
    return result;
}
bool CReserveKey::GetReservedKey(CPubKey& pubkey)