Update wrapper config for booleans to conform to Bootstrap 3 examples

The current bootstrap initializers for boolean (checkboxes) do not create the output as suggested by Bootstrap documentation. The checkbox itself is not even visible (at least in Chrome). I updated the wrappers so that the output is according to the documentation:

```
<div class="checkbox">
  <label>
    <input type="checkbox">Label text
  </label>
</div>
```