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.
private:
    const CKeyStore &keystore;
    std::vector<CKeyID> &vKeys;
public:
    CAffectedKeysVisitor(const CKeyStore &keystoreIn, std::vector<CKeyID> &vKeysIn) : keystore(keystoreIn), vKeys(vKeysIn) {}
    void Process(const CScript &script) {
        txnouttype type;
        std::vector<CTxDestination> vDest;
        int nRequired;
        if (ExtractDestinations(script, type, vDest, nRequired)) {
            BOOST_FOREACH(const CTxDestination &dest, vDest)
                boost::apply_visitor(*this, dest);
        }
    }
    void operator()(const CKeyID &keyId) {
        if (keystore.HaveKey(keyId))
            vKeys.push_back(keyId);
    }
    void operator()(const CScriptID &scriptId) {
        CScript script;
        if (keystore.GetCScript(scriptId, script))
            Process(script);
    }
    void operator()(const CNoDestination &none) {}
};
void CWallet::GetKeyBirthTimes(std::map<CKeyID, int64_t> &mapKeyBirth) const {