Fixed malformed Data URI

Removed a space from a URL in the form-select mixin that was causing
Ruby's URI.parse method to throw an error. Can't 100% guarantee that
spaces in data URIs are actually against spec, but my reading of RFC
2397 suggests they aren't, and it'll decode the same without the space
anyway.

Ran into the issue when using a gem (sinatra-assetpack) that attempts to
parse URLs in CSS to see if they can be "cache busted".
test travis
Create mixin for hamburger icon
Check if mixin is being used in offcanvas
Update _offcanvas.scss
Check if mixin is being used in offcanvas
Update _top-bar.scss
Update _top-bar.scss
Update _top-bar.scss
Update _top-bar.scss
Update _top-bar.scss
Allow false to be passed as abort_on_close option

Before as it was only looking to see if the abort var was defined or not you were unable to set the abort_on_close option to false and have the post callbacks trigger.
Update equalizer.html
Changed font weight definitions to variables.
Changed settings to reference font variables.
Update _tabs.scss

adds type to make tabs work in customizer or stand alone.
remove padding-right from topbar menu icon

The rule padding-right: 25px; at line 231 pushes the menu icon half way out of the topbar element, as can be seen at http://foundation.zurb.com/docs/components/topbar.html.
Removing the rule fixes it.
Fixes Issue #5116
Update _top-bar.scss

It is added an arbitrary 20px padding at the right of menu items with sub menus. This break the layout, it should be added only the standard $topbar-link-padding.
Update _accordion.scss

If the accordion .content div contains a div with the class .content, that div currently gets display:none and so is invisible

Solution: specify the accordion .content div as a child of the dd