Reformatted the type info displayed for method and event parameters

@ebidel @addyosmani 

Closes #27, with a live example at http://jeffposnick.github.io/core-doc-viewer/components/core-doc-viewer/demo.html#core-xhr.methods.request (and that link makes use of support for intra-page URL fragments!).

I'm happy to switch up the formatting, if you have any strong preferences re: wrapping the type in `<>` vs. something else, using `<em>`, etc.