Fix dropdown button positioning

-- Timing issues caused intermittent miscalculation of button height,
   resulting in inproper placement of dropdown. Ensuring dom is loaded
   fixes that.
Refactor hiddenFix and use it for button dropdowns

-- Button dropdowns rely on outerHeight to determine proper
   placement of list below button. When the button is hidden on
   the page, the calculation fails. Code to adjust for this
   already exists in foundation.forms.
-- Refactor "hiddenFix" from a private function inside foundation.forms
   to an object in a new module, foundation.utils.
-- Include foundation.utils in index.js so it's available to
   the rest of the codebase.
-- Use hiddenFix to properly calculate size of button dropdowns
-- Revert previous change of putting the caculation inside document
   ready.
Fix event propagation

-- Make sure the click is for the button and not one of it's
   children before stopping event propagation. This allows for
   users to have things other than links in the dropdown list.
Merge remote-tracking branch 'upstream/master'

Conflicts:
	vendor/assets/javascripts/foundation/jquery.foundation.buttons.js
Merge branch 'master' of https://github.com/zurb/foundation

Conflicts:
	vendor/assets/javascripts/foundation/jquery.foundation.buttons.js
added missing close bracket for .sticky class
added hover state back in for dropdowns
fixed conflicts