It seems that bitcoin{d,-qt} can be crashed by being sent an inv of an unknown type. At least, it caused mine to:-

```
2016-11-08 00:45:36.470 ProcessMessages(getdata, 397 bytes): CHECKSUM ERROR expected=6d9dbcdf was=a1046737 peer=39585
2016-11-08 00:45:36.481 

************************
EXCEPTION: St12out_of_range       
CInv::GetCommand(): type=1373179482 unknown type       
bitcoin in ProcessMessages()       

2016-11-08 00:45:36.482 ProcessMessages(getdata, 397 bytes) FAILED peer=39585
2016-11-08 00:45:36.487 

************************
EXCEPTION: St12out_of_range       
CInv::GetCommand(): type=1373179482 unknown type       
bitcoin in msghand       

```

If the `throw std::out_of_range(strprintf("CInv::GetCommand(): type=%d unknown type", type));` in protocol.cpp supposed to cause the program to end?
{
    return std::string(pchCommand, pchCommand + strnlen(pchCommand, COMMAND_SIZE));
}
bool CMessageHeader::IsValid(const MessageStartChars& pchMessageStartIn) const
{
    
    if (memcmp(pchMessageStart, pchMessageStartIn, MESSAGE_START_SIZE) != 0)
        return false;
    
    for (const char* p1 = pchCommand; p1 < pchCommand + COMMAND_SIZE; p1++)
    {
        if (*p1 == 0)
        {
            
            for (; p1 < pchCommand + COMMAND_SIZE; p1++)
                if (*p1 != 0)
                    return false;
        }
        else if (*p1 < ' ' || *p1 > 0x7E)
            return false;
    }
    
    if (nMessageSize > MAX_SIZE)
    {
        LogPrintf("CMessageHeader::IsValid(): (%s, %u bytes) nMessageSize > MAX_SIZE\n", GetCommand(), nMessageSize);
        return false;
    }
    return true;
}
CAddress::CAddress() : CService()