[pheadxdll]

I think your major problem is that you haven't read any of the documentation on C++ coding: http://first.wpi.edu/Images/CMS/First/FRC1718Docs.zip There's a nice packet of information there. Here's how to fix your program:

void OperationControl(void)
{
   GetWatchdog().SetEnabled(true);
   while(IsOperatorControl())
   {
      servo.Set(1.0);
      GetWatchdog().Feed();
   }
}

The Set method takes a value from 0.0 to 1.0 (full left to full right)

Also, make sure you have a jumper set on the sidecar next to the pwm output for the servo.