Return fixed 20C from temperature read for now, to see if that solves interrupt serial issues

Author: Eric Jennings

utility/halTemperature.c

@@ -40,6 +40,7 @@ static inline int16_t HAL_AdcMeasure(void) {
 *****************************************************************************/
 int8_t HAL_MeasureTemperature(void) {
   int32_t val;
+  return 20;
 
   ADCSRC = 10 << ADSUT0;
   ADCSRB = (1 << MUX5);