message: Implement matrices totals for vue,
diff: </thead>
  <thead v-if="showVerticalHeader">
  <tr>
  - <td v-if="this.question.showHeader"></td>
  + <th v-if="question.showHeader"></th>
  <th v-for="row in rows">
  <survey-string :locString="row.locText"/>
  </th>
  + <th v-if="question.showFooter"></th>
  </tr>
  </thead>
  <tbody v-if="isColumnsHorizontal">
  </button>
  </td>
  </tr>
  + <tr v-if="question.hasFooter">
  + <td v-if="!isDynamic"></td>
  + <td v-for="cell in question.visibleTotalRow.cells" :key="'footer_' + cell.question.id">
  + <survey-expression v-if="cell.column.hasTotal" :question="cell.question"/>
  + </td>
  + <td v-if="!canRemoveRow"></td>
  + </tr>
  </tbody>
  <tbody v-if="!isColumnsHorizontal">
  <tr
  v-for="cell in getCellsByColumn(columnIndex)"
  :key="columnIndex + '_' + cell.question.id"
  />
  + <td v-if="question.hasFooter">
  + <survey-expression
  + v-if="column.hasTotal"
  + :question="question.visibleTotalRow.cells[columnIndex].question"
  + />
  + </td>
  </tr>
  <tr v-if="canRemoveRow">
  <td v-if="question.showHeader"></td>
  