Add util to grok with display backlight brightness

scripts/brightness

@@ -0,0 +1,14 @@
+#!/bin/bash
+
+: ${1?"Usage: $0 argument"}
+
+brightness=`cat /sys/class/backlight/intel_backlight/brightness`
+max_brightness=`cat /sys/class/backlight/intel_backlight/max_brightness`
+new_brightness=`printf %.0f $(echo "$brightness*$1" | bc -l)`
+
+if [ $new_brightness -gt $max_brightness ] 
+then
+    new_brightness=$max_brightness
+fi
+
+echo $new_brightness > /sys/class/backlight/intel_backlight/brightness