Match an option in select form with boolean values

参考：https://stackoverflow.com/questions/11430969/match-an-option-in-select-form-with-boolean-values

f.select :active, [['Active', true], ['Inactive', false]]
将会得到：</p>
<select name="model[active]">
<option value="true">Active</option>
<option value="false">Inactive</option>
</select>