Report both pm25 *and* pm10, and average temperature across time

Report both pm25 *and* pm10, and average temperature across time

 * add pm10 as a discrete value, and create an overall struct to hold
   both data types (pmbuffer) and average
 * make the temp list an actual ring buffer too, for use in
   flattening/averaging out temperature values like is currently done on
   pico
 * memmem for searching a value worked better, and the strstr variant
   was buggy for whatever reason