trigger the seeked signal after seeking because due to a bug in jwplayer, it's
not triggered when the video was paused.
{{! template for the slice widget }}
<div class='Ldt-sliceWidget'>
{{! the whole bar }}
<div class='Ldt-sliceBackground'></div>
<div class='Ldt-sliceLeftHandle'></div>
{{! the zone which represents our slice }}
<div class='Ldt-sliceZone'></div>
<div class='Ldt-sliceRightHandle'></div>
</div>