Add the "Projects That Use ev3dev" page to the static site

I have added [a page](http://wasabifan.github.io/ev3dev/Projects) that we can use to link to other projects. It took a bit or rearranging of the nav links, but I got it to work. The page looks a bit sparse but I don't think that's a problem. Some points of discussion:
- Do we want to include a link to the projects page somewhere in the body of the home page, or is a link in the header enough?
- I included links to the previously discussed projects, but each link points to a different type of resource (YouTube, a GitHub code file, an issue comment, etc). Should I remove the ones that are there until those maintainers ask us to post their project, and specify the page that they want us to use?

I am open to suggestions, and I will happily change things if need be.