Customize asmSelect to allow text search and optgroup like in "chosen" - Repost

I have a slight customized asmSelect control, working with a bootstrap template, allowing me to select and order multiple options from a html select control. I'd like to add an embedded search box and optgroup like in "chosen". A stripped working html page is provided in attach. Images show how the control is now and how I'd like to have, with also a search box (not shown in the "[login to view URL]") and the ability to divide the options in multiple sections with header, not selectable. The items selected need to be sent in the POST action of the form as ordered arrays, like it happens for the original asmSelect, so no code change will be needed on my side.