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.
{
        pwallet = pwalletIn;
        MarkDirty();
    }
    
    CAmount GetDebit(const isminefilter& filter) const;
    CAmount GetCredit(const isminefilter& filter) const;
    CAmount GetImmatureCredit(bool fUseCache=true) const;
    CAmount GetAvailableCredit(bool fUseCache=true) const;
    CAmount GetImmatureWatchOnlyCredit(const bool& fUseCache=true) const;
    CAmount GetAvailableWatchOnlyCredit(const bool& fUseCache=true) const;
    CAmount GetChange() const;
    void GetAmounts(std::list<COutputEntry>& listReceived,
                    std::list<COutputEntry>& listSent, CAmount& nFee, std::string& strSentAccount, const isminefilter& filter) const;
    void GetAccountAmounts(const std::string& strAccount, CAmount& nReceived,
                           CAmount& nSent, CAmount& nFee, const isminefilter& filter) const;
    bool IsFromMe(const isminefilter& filter) const
    {
        return (GetDebit(filter) > 0);
    }
    
    bool IsEquivalentTo(const CWalletTx& tx) const;
    bool InMempool() const;
    bool IsTrusted() const;
    int64_t GetTxTime() const;
    int GetRequestCount() const;
    bool RelayWalletTransaction(CConnman* connman);
    std::set<uint256> GetConflicts() const;
};
class COutput