twitter/bootstrap — pull request #6048 by blakeembrey (2012-11-28 20:49:31+00:00)
Title: Dropdowns update - keyboard, touch and submenus

Fixes:

* Keyboard navigation using submenus (acts similar to right-click in Mac, going up first starts to top of list, bottom the bottom - moves from there, etc. Only difference is that the submenus display on item focus)
* Takes into account the `.dropup`, `.dropdown` and `.pull-left` modifier classes. E.g. If it's pull-left the left and right arrows switch around, if it's a dropup submenu - we start by focusing the last item vs the first which is at the top.
* Touch navigation now works prevents the default click events from happening with the delay
* [esc] key will bring you back in focus with the initial button no matter where in the dropdown you are
* Adds a item visibility selector to only navigate through visible items