Forked from https://bitbucket.org/blackBriar/wattmeter and https://github.com/luispabon/gnome-shell-battery-time-and-percentage
Simple extension to show current power consumption in Gnome battery widget.
Differs from original wattmeter -- it reads directly from /sys/class/power_supply/BAT0/power_now.
Tested with ThinkPad Carbon X1 Gen4