added an option to force the redraw of a list, even if the cached lists are the
same (which is the case when we just added another annotation)
<div class='Ldt-sparklineWidget' style='width: {{width}}px; height: {{height}}px'>
<div class='Ldt-sparkLinePositionMarker' style='width: 0px; height: {{height}}px'></div>
<div class='Ldt-sparkLineClickOverlay' style='width: {{width}}px; height: {{height}}px'></div>
<div class='Ldt-sparkLine' style='width: {{width}}px; height: {{height}}px'>Loading</div>
</div>