i3bar: change default colors to fit the i3 look & feel

i3bar: change default colors to fit the i3 look & feel

The new default looks like this (like in docs/userguide):

	colors {
		background #000000
		statusline #ffffff
		focused_workspace  #ffffff #285577
		active_workspace   #888888 #222222
		inactive_workspace #888888 #222222
		urgent_workspace   #ffffff #900000
	}

If you want to go back to the previous colors, use:

	colors {
		background #000000
		statusline #ffffff
		focused_workspace  #ffffff #480000
		active_workspace   #ffffff #480000
		inactive_workspace #ffffff #240000
		urgent_workspace   #ffffff #002400
	}