By adding a int i_nExtraWidth parameter to the layoutButton function
there will be enough space for the open button and its black triangle.

special thanks to Stephan for the configuration part

It turns out this new idea of mapping xinerama screens, and xrandr
monitors into a flat integer space is nice, but when we confuse
xrandr monitor 2 (idx 1) with X screen 1 (there is only one screen)
we bit the dust.

Many thanks to Cor Nouws for remote debugging assistance