Fix the hidden bug when RpcBase was restart

[JamesLebron]

Submit found bugs

[c-jimenez]

Thanks for submitting these fixes, I will review them this week.

[c-jimenez]

Hi,

I won't take the fix concerning the DateTime object since it seems that it is working fine with other timezone than UTC.
A thing that you may have missed is that it always returns an ISO-8601 string for UTC time (ends with 'Z' timezone) not for local time, hence the use of the gmtime_r function and the computation of the time offset tm_gmtoff.

You may use this simple test program to convince yourself :

 int main()
{
    setenv("TZ", "EST5EDT", 1);
    tzset();
    std::cout << tzname[0] << std::endl;
    std::cout << tzname[1] << std::endl;
    
    DateTime now = DateTime::now();
    
    std::cout << now.str() << std::endl;
    
    DateTime now2;
    if (now2.assign(now.str()))
    {
        std::cout << now2.str() << std::endl;    
    }
    else
    {
        std::cout << "Oupsie!" << std::endl;
    }
}