Update 2011-01-28-what-is-a-view.md

Hi,

This is my first time really working through backbone.js. I was running through the tutorial with underscores 1.7.0 and spent a little while headbanging as to why this wasn't working and found that it was because ay underscores.js handles templates differently in version 1.7.0 (http://underscorejs.org/#changelog).

I'm a bit of a noob when it comes to JS so please correct me if I've termed something wrong, but seemed like an easy enough fix.

Seems like https://github.com/thomasdavis/backbonetutorials/pull/115 fixed some other references to this as well.