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)

// Progress bars

.progress-bar-variant(@color) {
  background-color: @color;

  // Deprecated parent class requirement as of v3.2.0
  .progress-striped & {
    #gradient > .striped();
  }
}