Implemented timerange for mdplayer and use of it in widget Segment: if enable (option is use_timerange) when clicking a segment user can only read the video on current segment + adapted other widgets that need to detect segment to be able to use this option if it is enable so that segment detection is smoother + adjusted API testing form on iframetesting to use the correct api (form is still hidden by default)

// Horizontal dividers
//
// Dividers (basically an hr) within dropdowns and nav lists

.nav-divider(@color: #e5e5e5) {
  height: 1px;
  margin: ((@line-height-computed / 2) - 1) 0;
  overflow: hidden;
  background-color: @color;
}