Update bmp280_example.ino

add some comments to make codes more clear.

example/bmp280_example/bmp280_example.ino

@@ -44,18 +44,23 @@ void setup()
 void loop()
 {
   float pressure;
-
+  
+  //get and print temperatures
   Serial.print("Temp: ");
   Serial.print(bmp280.getTemperature());
-  Serial.println("C");
-
+  Serial.println("C"); // The unit for  Celsius because original arduino don't support speical symbols
+  
+  //get and print atmospheric pressure data
   Serial.print("Pressure: ");
   Serial.print(pressure = bmp280.getPressure());
   Serial.println("Pa");
-
+  
+  //get and print altitude data
   Serial.print("Altitude: ");
   Serial.print(bmp280.calcAltitude(pressure));
   Serial.println("m");
+  
+  Serial.println("\n");//add a line between output of different times.
 
   delay(1000);
 }