This is a new API for tooling to call to get a RazorTemplateEngine that's
initialized correctly. For now this is hardcoded to use MVC's conventions.
This is also a very temporary design to get us past the next wave of
changes.
We'll eventually want to change this to an ILanguageService, but this will
require some new plumbing in the editor, so let's defer that for another
day.
(cherry picked from commit a73b5f58a8713076433d24668b99705388b6d6b3)
Ryan Nowak