bs3 Make TbFormInputElement consistent with parent CFormInputElement:

Make TbFormInputElement consistent with parent CFormInputElement:
1. add $coreTypes. Note that this change is NOT backwards compatible (although previous behavior was undocumented).
2. use class or path alias as $type.

With these changes you can use TbForm in the same manner as original CForm:
```php
'elements' => array(
    'name' => array('type' => 'text'),
    'date' => array('type' => 'zii.widgets.jui.CJuiDatePicker'),
),
```