Update to 0.4

Update includes refinement of particular headers, consistency with a
break at the end of all pages, and new Carousel for featured progress!
There are currently two different Carousels on the front page, one
contains converted BYOB3 projects, and the other contains converted
Scratch projects. Each contain 5 unique projects, each repeated 4 times
in order to demonstrate functionality. Readme has also been updated to
reflect changes.