Remove highlight.js submodule.
Move to submodule from https://github.com/hitsthings/highlight.js
#53: Use new highlight.js clone to fix Scala multiline issue.
#54: Expose slide object in showSlide and hideSlide events.
Change from one-way to two-way navigation synchronization between original/parent/opener and cloned slideshow.
Add page-based fullscreen toggling.
Update to version 0.5.5.