Issue 98: Comment reply to entries

@mjangda Opening a pull request to review the work I've done so far. The primary remaining piece I have is to render the comment replies under each liveblog comment, and filter them out from appearing in the primary comment list below.

Question: Will comment replies be streamed in as they get added just like the author's liveblog comments? Or will new comments only be updated as the page reloads? I assume the former.

Question: Will the user comments be hidden by default with a link to expand them?

Question: Should the comment replies be nestable? Or should they only be able to have the liveblog comment as their only possible parent?

Will fix Automattic/liveblog#98

![screen_shot_2013-07-09_at_2 23 24_am](https://f.cloud.github.com/assets/134745/767199/9709bb1c-e879-11e2-8e81-e16dfd5e59f3.png)