addmultisigaddress creates an address respecting the setting, being unable to generate a specific type of address without also adding it to the wallet seems wrong.

I suppose in the future `addresstype` may be refactored to be wallet-specific, which would leave this non-wallet rpc call without an argument. Perhaps there should just be an optional parameter to set it.
{
    if (!mapAddressBook[dest].destdata.erase(key))
        return false;
    return WalletBatch(*database).EraseDestData(EncodeDestination(dest), key);
}
bool CWallet::LoadDestData(const CTxDestination &dest, const std::string &key, const std::string &value)
{
    mapAddressBook[dest].destdata.insert(std::make_pair(key, value));
    return true;
}
bool CWallet::GetDestData(const CTxDestination &dest, const std::string &key, std::string *value) const
{
    std::map<CTxDestination, CAddressBookData>::const_iterator i = mapAddressBook.find(dest);
    if(i != mapAddressBook.end())
    {
        CAddressBookData::StringMap::const_iterator j = i->second.destdata.find(key);
        if(j != i->second.destdata.end())
        {
            if(value)
                *value = j->second;
            return true;
        }
    }
    return false;
}
std::vector<std::string> CWallet::GetDestValues(const std::string& prefix) const