message: Fix Component description in examples
diff: <td>Container for the expandable content inside the panel.</td>
  </tr>
  <tr>
  - <td>mdl-expansion-panel-content-body</td>
  + <td>mdl-expansion-panel-body</td>
  <td>Defines the collapsible content for the panel</td>
  </tr>
  <tr>
  