The renderer now only stores the positions of the actions because that
is specific to the renderer and because the actual position can only be
finalized after all the rendering is done because intitially the
positions are relative to the alignment and not the bar.
The variables storing the current colors, attribute activations and font
were only used in a single place and can easily also be read from the
context.
This allows us to remove a lot of the state of the renderer.
