Add Type support to HTML render.

I was trying to do #112, at least for my custom template. I found that there are issues at least in c++ where `vector<int>` would not render correctly in HTML (need to strip `< >` into `&lt;&gt;`). So I thought I would just add support for Type objects to the HTML renderer...

It turned out to be a complicated task, I had to modify LanguageManager to give access to the language renderer and TemplateEngine to pass the current language to the HTML renderer.

The type renderer works like this:
* `Type;html` : Strips HTML characters from the rendered Type  name if necessary.
* `Type;html(java)` : First renders the type using Java's renderer, then strips HTML characters.
* `Type;html(cpp)` : First renders the type using c++'s renderer, then strips HTML characters.
* (Same with the other language names as defined in Language.java)