Add arbitrary attributes to form helper fields

[Colonel_mortis]

I found myself needing to add autocomplete="off" and autofocus attributes to a form element for a plugin, and the only way to do it was to create an entire new form helper that extends the type that I want, and a template to go with it. it would be great to be able to add 'attributes' => array ('autocomplete' => 'off', 'autofocus' => ''); in the options array, and for that to do it for me.