AC_PID: fixed example sketch's compile errors

libraries/AC_PID/examples/AC_PID_test/AC_PID_test.pde

@@ -39,7 +39,7 @@ void setup()
 void loop()
 {
     // setup (unfortunately must be done here as we cannot create a global AC_PID object)
-    AC_PID pid(0, PSTR("TESTPID_"),  TEST_P, TEST_I, TEST_D, TEST_IMAX * 100);
+    AC_PID pid(TEST_P, TEST_I, TEST_D, TEST_IMAX * 100);
     uint16_t radio_in;
     uint16_t radio_trim;
     int error;