Used new WPILIB2015 macro to mark differences with the old WPILib.

Change-Id: I9e45a22096bdb108f74f9dc341037d5f64506ff5
diff --git a/bot3/wpilib/wpilib_interface.cc b/bot3/wpilib/wpilib_interface.cc
index cc340cb..685b125 100644
--- a/bot3/wpilib/wpilib_interface.cc
+++ b/bot3/wpilib/wpilib_interface.cc
@@ -116,7 +116,12 @@
     ::aos::SetCurrentThreadName("SensorReader");
 
     my_pid_ = getpid();
-    ds_ = DriverStation::GetInstance();
+    ds_ =
+#ifdef WPILIB2015
+        DriverStation::GetInstance();
+#else
+        &DriverStation::GetInstance();
+#endif
 
     LOG(INFO, "Things are now started\n");