anchor.diff:                                      <div class="col-md-12">
                                           <div class="input-group">
                                               <span class="input-group-addon glyphicon glyphicon-pencil"></span>
  -                                            <input type="text" class="form-control" placeholder="Last name">
  +                                            <input id="last_name" type="text" class="form-control" placeholder="Last name">
                                           </div>
                                       </div>
                                   </div>
  
positive.code:                                     <div class="col-md-12">
                                          <div class="input-group">
                                              <span class="input-group-addon glyphicon glyphicon-pencil"></span>
                                              <input type="text" class="form-control" placeholder="First name">
                                          </div>
                                      </div>
                                  </div>
  
negative.code:                                     <div class="col-md-12">
                                          <div class="input-group">
                                              <span class="input-group-addon glyphicon glyphicon-home"></span>
                                              <input id="city" type="text" class="form-control" placeholder="City">
                                              <span class="input-group-addon"></span>
                                              <input id="street" type="text" class="form-control" placeholder="Street">
                                              <span class="input-group-addon"></span>
                                              <input id="building_number" type="text" class="form-control" placeholder="Building number">
                                              <span class="input-group-addon"></span>
                                              <input id="postcode" type="text" class="form-control" placeholder="Postcode">
                                          </div>
                                      </div>
                                  </div>
  