legacy: add form type "radio" & "radio_br"
legacy: add form type "checkbox", "checkbox_br" & "group_checkbox"
legacy: add form type - fix checked status of checkbox
remove form_type radio_br & checkbox_br
fix typo in preference_edit.html L.101
Merge pull request #59 from nao-pon/pref_form

add Pref formtype radio, checkbox & group_checkbox