MDL-31830 course: fixed up minor points as noted by Damyon's integration review

* Fixed typo breaking drag and drop of courses.
* Fixed the ' ' title for the create new button plus two other icons I found as well.
* Adding padding to items displayed in the action menu drop down. base + bootstrapbase.
* Padding adjusted to the same as on the course page. base + bootstrapbase.
* Removed hover icon from categories. base only.
* Fixed categroy typo
* Removed min-width that was being applied to coursename making its clickable area larger than normal.
* The category tree is now presented using aria attributes as per http://www.w3.org/WAI/GL/wiki/Using_ARIA_trees
* Bulk action selectors now use aria-labelledby
* Category course count now given access hidden label.
* Pagination links now have better titles.
* The course action icons now present with role=button