Gets the element's type.
Possible values include:
$w.TextInput
$w.TextBox
$w.RichTextBox
$w.RadioButtonGroup
$w.CheckboxGroup
$w.Dropdown
$w.SelectionTags
$w.Slider
$w.DatePicker
$w.UploadButton
$w.RatingsInput
$w.AddressInput
$w.Switch
$w.SignatureInput
$w.Captcha