Handle language templates

If a question has a template, use it instead of the blank editor when opening a new question.

It would be super cool if we found a way to use Ace's snippet format for expanding these for the best support. In lieu of that, be sure to make `$1` be removed and have the cursor placed there.

Start by locating the new-question flow and how language templates and the Ace editor are initialized. Verify that a template replaces the blank editor, that `$1` is removed, and that the cursor is placed at its position; Ace snippet-format support is an optional direction mentioned by the issue.

Written by the indexing model from the issue text.