Adding stowballs media query mixins
Added example of how to use media-query-bp mixin
Re-writing responsive breadcrumb in native JS

As part of jQuery removal work, re-writing responsive breadcrumb in
native JS
Fix non-jQuery responsive breadcrumb
Merge pull request #46 from malarkey/wip

Adding stowball's media query mixins, documenting the media-query-bp mixin, updating font-size mixin, responsive-breadcrumb is now non jQuery