Update _768up.less

I was working with bones and found a small error under navigation, 'li.current-page-ancestor' should be 'li.current_page_ancestor' (2 occurrences).

I am new to programming, learning to make wordpress themes. :)
Fix accessibility issue in the menu and cleaned up some CSS.
fix classname li.current_page_ancestor

It was li.current-page-ancestor before. wordpress uses li.current_page_ancestor
Minor Inconsitency
Merge pull request #515 from blowsie/patch-6

Minor Inconsitency
Merge pull request #500 from elron/patch-21

fix classname li.current_page_ancestor
Merge pull request #491 from bgallagh3r/master

Fix accessibility issue in the menu and cleaned up some CSS.
Merge pull request #415 from gthapar/patch-1

Update _768up.less
Update functions.php

Added ability to use dropdown menu from media manager when someone adds an image in the content block.
Merge pull request #545 from sixfootjames/patch-1

Update functions.php
Update _normalize.less
Update _normalize.scss
Re-added customized reset values
Re-added customized reset values to LESS
Merge pull request #548 from PxlBuzzard/master

Updated normalize.css for LESS and SCSS