Increasing accuracy of Puck.light()

@Gordon, Puck.light() is returning lower values than expected after the first call. Probably because I'm lighting up LED1.

Short story: I think this can be fixed by extending the settling time delay in jswrap_puck_light().

I type this in the console, and I get:

>LED1.write(1);
=undefined
>LED1.write(0);
=undefined
>Puck.light()
=0.15357589721
>Puck.light()
=0.55925130844
>

The last 0.559 reading is the most accurate.

Here's my workaround that gives consistent light readings:

var checkLight = function(){
  digitalWrite(LED1,0);
  analogRead(LED1);
  delay(50);
  light = analogRead(LED1) * NRF.getBattery() / (3 * 0.45);
  light = Math.round(light * 100);
  if (light < 20){
    console.log("  Seems pretty dark in here: " + light + "% brightness");
  } else {
    console.log("  Seems light in here: " + light + "% brightness");
  }
};

var delay = function(milliseconds){
  // Always try to use setTimeout or setInterval instead
  // of this function. This function, used for long periods
  // uses battery power!
  
  var timeout = new Date().ms + milliseconds;
  while(new Date().ms < timeout);
};

Like your C code for jswrap_puck_light(), I reset the LED1 pin, take a reading, wait, and take another (better) reading. But I wait 50 milliseconds, rather than 5 milliseconds.