Default
checked="checked"
disabled="disabled"
checked="checked"
value="mixed" disabled="true"
disabled="disabled" checked="checked"
readOnly = "true" checked = "checked"
value="mixed"
value="true"
value="false"
value="true" attr('disabled', true)
value="mixed" attr('value', 'true')
new idx.form.TriStateCheckBox & different alt per state