From what I can tell `CClientUIInterface::[signal_name]_disconnect` is a no-op.

In other words calling it does *not* disconnect the slot:

For example `uiInterface.NotifyBlockTip_disconnect(BlockNotifyGenesisWait);` in `AppInitMain(...)` does not disconnect `BlockNotifyGenesisWait` as one would expect. The result being that `BlockNotifyGenesisWait` is invoked for every new block :-)

Running `bitcoind` with some debug printing added shows the issue:

```
[signals] CClientUIInterface::ThreadSafeMessageBox_connect(...) entered with 0 connected slots.
[signals] CClientUIInterface::ThreadSafeMessageBox_connect(...) exited with 1 connected slots.
[signals] CClientUIInterface::ThreadSafeQuestion_connect(...) entered with 0 connected slots.
[signals] CClientUIInterface::ThreadSafeQuestion_connect(...) exited with 1 connected slots.
[signals] CClientUIInterface::InitMessage_connect(...) entered with 0 connected slots.
[signals] CClientUIInterface::InitMessage_connect(...) exited with 1 connected slots.
[signals] CClientUIInterface::InitMessage_connect(...) entered with 1 connected slots.
[signals] CClientUIInterface::InitMessage_connect(...) exited with 2 connected slots.
[signals] Calling uiInterface.NotifyBlockTip_connect(&RPCNotifyBlockChange) in OnRPCStarted()
[signals] CClientUIInterface::NotifyBlockTip_connect(...) entered with 0 connected slots.
[signals] CClientUIInterface::NotifyBlockTip_connect(...) exited with 1 connected slots.
[signals] Calling uiInterface.NotifyBlockTip_connect(BlockNotifyGenesisWait) in AppInitMain(...)
[signals] CClientUIInterface::NotifyBlockTip_connect(...) entered with 1 connected slots.
[signals] CClientUIInterface::NotifyBlockTip_connect(...) exited with 2 connected slots.
[signals] RPCNotifyBlockChange(...) was invoked.
[signals] BlockNotifyGenesisWait(...) was invoked.
[signals] Calling uiInterface.NotifyBlockTip_disconnect(BlockNotifyGenesisWait) in AppInitMain(...)
[signals] CClientUIInterface::NotifyBlockTip_disconnect(...) entered with 2 connected slots.
[signals] CClientUIInterface::NotifyBlockTip_disconnect(...) exited with 2 connected slots.
[signals] RPCNotifyBlockChange(...) was invoked.
[signals] BlockNotifyGenesisWait(...) was invoked.
[signals] RPCNotifyBlockChange(...) was invoked.
[signals] BlockNotifyGenesisWait(...) was invoked.
[signals] RPCNotifyBlockChange(...) was invoked.
[signals] BlockNotifyGenesisWait(...) was invoked.
... and so on ...
```

Note how `BlockNotifyGenesisWait(...)` is called also after `uiInterface.NotifyBlockTip_disconnect(BlockNotifyGenesisWait)`.

I think the problem is that the `disconnect(...)` member function of `boost::signals2::signal` expects a function pointer to be passed in (the same that was passed to `.connect(...)`), but we're doing:

```
void CClientUIInterface::signal_name##_disconnect(std::function<signal_name##Sig> fn)
{
    return g_ui_signals.signal_name.disconnect(&fn);
}
```
uint64_t nMaxOutboundLimit = 0; 
    uint64_t nMaxOutboundTimeframe = MAX_UPLOAD_TIMEFRAME;
    if (gArgs.IsArgSet("-maxuploadtarget")) {
        nMaxOutboundLimit = gArgs.GetArg("-maxuploadtarget", DEFAULT_MAX_UPLOAD_TARGET)*1024*1024;
    }
    
    fReindex = gArgs.GetBoolArg("-reindex", false);
    bool fReindexChainState = gArgs.GetBoolArg("-reindex-chainstate", false);
    
    int64_t nTotalCache = (gArgs.GetArg("-dbcache", nDefaultDbCache) << 20);
    nTotalCache = std::max(nTotalCache, nMinDbCache << 20); 
    nTotalCache = std::min(nTotalCache, nMaxDbCache << 20); 
    int64_t nBlockTreeDBCache = std::min(nTotalCache / 8, nMaxBlockDBCache << 20);
    nTotalCache -= nBlockTreeDBCache;
    int64_t nTxIndexCache = std::min(nTotalCache / 8, gArgs.GetBoolArg("-txindex", DEFAULT_TXINDEX) ? nMaxTxIndexCache << 20 : 0);
    nTotalCache -= nTxIndexCache;
    int64_t nCoinDBCache = std::min(nTotalCache / 2, (nTotalCache / 4) + (1 << 23)); 
    nCoinDBCache = std::min(nCoinDBCache, nMaxCoinsDBCache << 20); 
    nTotalCache -= nCoinDBCache;
    nCoinCacheUsage = nTotalCache; 
    int64_t nMempoolSizeMax = gArgs.GetArg("-maxmempool", DEFAULT_MAX_MEMPOOL_SIZE) * 1000000;
    LogPrintf("Cache configuration:\n");
    LogPrintf("* Using %.1f MiB for block index database\n", nBlockTreeDBCache * (1.0 / 1024 / 1024));
    if (gArgs.GetBoolArg("-txindex", DEFAULT_TXINDEX)) {
        LogPrintf("* Using %.1f MiB for transaction index database\n", nTxIndexCache * (1.0 / 1024 / 1024));
    }
    LogPrintf("* Using %.1f MiB for chain state database\n", nCoinDBCache * (1.0 / 1024 / 1024));
    LogPrintf("* Using %.1f MiB for in-memory UTXO set (plus up to %.1f MiB of unused mempool space)\n", nCoinCacheUsage * (1.0 / 1024 / 1024), nMempoolSizeMax * (1.0 / 1024 / 1024));
    bool fLoaded = false;
    while (!fLoaded && !ShutdownRequested()) {